My 4 speed Hatch has no tachometer, how would I go about installing one?

[SnatchedHatch]

My cluster only has a speedometer and the subaru car HUD (4wd, parking brake, etc). I kind of wish I had a tachometer.

 

If anyone had a spare cluster like this, I'm willing to buy it. Anyone know if it's plug and play? Would it be easier to buy an aftermarket tach gauge to stick somewhere on the dash?

 

Thanks