From what I can tell, it's a regular car with a regular drivetrain, without significant modifications. Others may disagree, but with a regular, non-modified car, that you are not trying to do anything special with (drag racing, autocross, fancy shows), you are almost always (there are always exceptions in life) better off with dead-stock parts, preferably, these days, older-stock, non-Chinese parts.
Also, you don't sound like someone with a lot of experience with older cars, so you will have the easiest time understanding and fixing it if you stick to regular factory parts, the function and repair of which is completely covered in the service manual.
Based on what we've seen in your posts, it looks like the your car has been touched by the hands of the most dreaded, feared, and hated individual in the entire collector car world:
The Previous Owner.
There is no more evil character in the annals of motoring, and you will now come to understand his destructive powers and to detest the foul stench of his work.
Rip all that crap out.
Also, does your ammeter work? Based on what we've seen, there is probably f*ckery afoot in the electrical system, which could melt wires and/or your ammeter, and start a fire.
Beware.
– Eric