You might investigate a propane/butane mix. From what I have read, not as dangerous as it 'sounds'.....I mean, you have 10+ gallons of gasoline in the car anyway.
that's the classic symptom of the 'cardan' joint (u-joint) on the steering shaft going bad. To prove it, spray some light lube or even PB Blaster on the joint to see if it (temporaily) gets better.
How many miles on the alternators? They typically wear out a brush right around 150k miles, causing low output. I've rebuilt several of the alternators since 1988, 150k is very repeatable. A couple of times the internal regulator or the rectifiers died.