No insult was intended in my post.
Nor in mine, merely trying to be realistic.
For many years I was constantly faced with similar problems, as were many of my technicians. In some cases we went ahead and repaired or rebuilt old systems and hardware, after consulting with the customer and getting his go-ahead, usually because for some reason or other the customer was dependent on it for compatibility, a specific function, or some other reason.
In the majority of cases, the cost of troubleshooting old hardware and setting up systems using it, is more than the cost of a new system, often very considerably more.
Private individuals can spend as much time as they like in attempting repairs or builds like this using old stuff, and if you play around with some things long enough you may get them to work, or you may not. If any of the parts are defective, then you wont.
If you do not know which parts may be defective then you also wont, because it makes no difference how you assemble them, the resulting system will not work.
The OP stated that he did not want to spend any more money on the project. Without some new parts of good quality and provenance it is unlikely that the project will succeed. This is mainly because there is no way of knowing which parts may be defective, and the OP has no way except trial and error to test that.
The possible combinations of defective hardware are more or less infinite.
Changing any one component is extremely unlikely to solve the basic problem. You have to KNOW which parts are defective.
Finding one defect in a running computer system is not usually all that difficult. Common sense and logic will usually suffice. Finding two defects which occur simultaneously is a lot harder, finding more defects is impossible without a baseline or a way of checking the components and software concerned.
Finding possible multiple defects in a "system" which will not run at all, is impossible without the right gear. Changing any one component at random is pointless. Not least because if you do that it might well be the last component you change that finally solves the issues. So you might just as well have changed them all to begin with. In the meantime you might well have damaged some of the new components as a result of combining them with old and possibly defective hardware.
Trying to diagnose things without a baseline and the wherewithal to do so is impossible. There is no way to know what works and what doesn't.
Trying to do so is invariably a futile endeavour.
Pointing this out to somebody who is trying it, because he is not aware of the problems involved, is of much greater help than suggesting random hardware changes.
Regards....Mike Connor