Numbchux

Yep, I've done a few variations of that on several vehicles.

I assume so, I'd have to study to remember. But almost certainly switch to ground.

That's true of the main oil pressure switch. But he said "on the head". The VVT switches thread right into the head casting. If that cracks, it's no small project to repair. Yes, BSP pipe thread, which is tapered to help it seal. It should not bottom out. Thread sealant of some sort should be added.

The VDC models had side airbags in the seat. To my knowledge, none of these models were available with cloth seats AND side airbags. You could probably put a resister in the connector to make the system think the side airbags were present, and then you'd have the same protection as the other models. But definitely something to be aware. Off the top of my head, I think the Outback ones will likely all be tan interior. You can get a Legacy L one with All-Weather package and gray cloth, but it will likely not be power. Passenger seats are all manual, but again I think you'll sacrifice the side airbag. Rear seats should all be interchangeable within body style (wagon vs sedan vs Baja), maybe even across. I put a back seat from a '98 OBK Wagon into a '99 OBK Sedan years ago. The cushion was a touch different, but it bolted right up, and looked better than the torn one that was there.

Pretty sure there's a neutral switch on the transmission, if you wanted to use it. But yea, clutch switch is fine

I had a similar issue on my 35th anniversary car (2004). Critters had gotten into the left rear quarter panel and chewed the wiring harness. Shorting the turn signal circuit to the LR light, and damaging the wiring to the antenna (I think your 2000 will have a conventional antenna on the roof over the driver's door). Every time I used the Left turn signal, the gauge cluster would go dead. As long as I remembered not to use that signal, things were cool. If you can't think of a more specific correlation between using a function like that and the failure, I'd buy a breaker for that fuse so it could be reset and continue on. Hope that helps!

Could be a few things. Usually a driveshaft or sticking caliper will be effected by throttle/brake use, but not always. If putting the FWD fuse in makes it go away, it's likely driveshaft or rear axle related. If it's a sticking caliper, spending some time at speed and then gently stopping will leave one brake VERY Hot (like, just hold your hand in front of the wheel, you'll feel it. Don't touch the rotor!) Inspect all suspension bushings. Control arms, ball joints, tie rods and ends, steering rack bushings, etc. A combination of a slightly out of balance tire and a couple of old bushings, for example, can turn into a pretty good wobble.

Oops, didn't catch the reference about starting when I messaged you. The neutral wire on the ECU doesn't control whether it will start or not. It raises the idle, changes timing, and a few other small things to keep it from stalling. If the ECU thinks it's always in gear, the engine can stall when clutch in. In case anyone else is looking for this info. Starter wire needs 12v while cranking, It can be spliced in anywhere between the ignition switch and starter. Most fuel injection cars will have an existing splice in there for this purpose. Also there's an AT/MT identifier pin on these earlier ECUs. Grounded for one, open for the other. I don't remember which but it's been documented on here.

Pretty common to have other warning lights come on with the battery light. Our Honda Odyssey lights up like crazy when the alternator quits. That diode in the cluster prevents it from working the other way, though.

Was this happening before the alternator replacement? define "brand new alternator"....OEM? Reputable aftermarket? Parts store cheapy? Those lights are controlled by the alternator, supposed to indicate charging failure. If the lights are on and alternator is still charging, I think it would have to be a faulty alternator.

I'm really not sure what color, or how it was wired on the EA82. When I made swap harnesses from 90-94 Legacy donors, I would run a separate wire back to the ECU and tie it in to the small circuit that comes straight from the ignition switch (fuel pump relay, ECU, and ignition coil? I think?). And I definitely don't remember how I did the FrankenWagon.....definitely not "correctly". But it worked, mostly.

I sort of skimmed over this, so forgive me if I missed it. Trouble Codes? These OBDI ECUs are pretty limited, but they can still trigger and display trouble codes. Please tell me you've pulled those before throwing all these parts at it. The ECU should be grounded via the engine harness to the block. There are likely a few eyelets in various places on the block and intake. Engine harness should not be grounded to the chassis, as any resistance between there and the block will skew the data coming from any engine sensors that do not have their own ground. Where is the alternator voltage reference tied in? On the same circuit as the ECU? This probably isn't the issue unless there's 15ft of undersized wire between the alternator plug and ECU. On my first EJ22 swap (92 Legacy into 92 Loyale, nearly 20 years ago now) I had issues with it stumbling and hesistating randomly for awhile. Finally I was able to catch it starting and stopping when I moved the wires for the crank sensor. I ran new wires (unshielded, intended to be temporary) and it never did it again, probably went about 100k after the swap before 3 owners after me crashed it.

Yea, sometimes grease isn't thick enough and will push past the ball bearings. A slice or 2 of bread actually works better.

B/W is for the light. This must be connected for the alternator to charge. It can be fooled with a resistor with similar resistance as the bulb to 12v. Yellow is for the voltage reference. Wherever you connect this to, the alternator will target 14.5v at. In the OE config, it's tapped into an ignition switched engine fuse in the cabin. That's how it should be done. That said, the results would be acceptable to tap it into a switched power wire just about anywhere, but it might not be as effective at compensating for voltage drop, and therefore might not charge the battery as effectively.

Yep, been done many times. Start here: I compiled all of the information I could find at the time into a pdf after completing my first, nearly 20 years ago. It's still available there. There are hundreds of combinations and approaches to do this, depending on your budget, skills and goals. Some of what we did then involves parts that are basically impossible to find now. Reliable daily? Drag Racing? Circuit? Ice racing? Rally? Mudding? Sand dunes? Rock crawling? It's all been done.