Click on "Buy Parts" above. I think the steering shock is only $25 and takes all of 15 minutes to replace. The flex disk is a little harder to replace, I haven't done one yet, but from what I understand they're pretty straightforward, definitely something you can DIY in a couple hours. I believe the price is $75 on one of those. If you are supplying free labor, these repairs should run you about $100. If you have to pay someone to do them, it could easily quadruple or worse.

Sounds like a bad tire. Try switching the tires from front to back and see if the problem moves to the rear of the car. If the car sat for a long time, the tires could be flat spotted.

Bad tires can cause all sorts of problems, and the tires on a used twenty year old car are very suspect.

when the vibration starts, carefully shift the car to neutral (taking your foot off the gas, of course) and let the engine drop to idle. If the problem is engine-related, the problem will go away.

i have done many engine swaps and with few exceptions they have worked out very well.i think that previous post gave good advice so that you can see that the engine is not the cause.generally speaking if the engine vibrates it will do it at low rpms and get worse as the revs climb.replace the steering shock and balance/move the wheels until you find the issue.

FIRST thing to do is check the wheels/tires for imbalance.