I think everyone prolly has an opinion on this.. The first thing I do when I acquire an old car is go into a cleaning mode.. it's also a discovery journey as well. I've found old spare parts, old coins, spiders,mice, you name it,I've found it! Once I found a newspaper about the JFK assanation. But,I usually clean (shop vac,mostly) and inspect the condition of things such as wiring,obsolete parts that's nearly impossible to get any more, along with what the possibility of repairing or building the offending part into something that will work on a sort of temporary situtation until a new part can be obtained. Rust seems to be the biggest culprit.. What usually stops the build/restoration is money. I won't take anything apart if I dont have the parts to reassemble it back. That's what slows me down and drains the fun out of doing car work. Lack of funds.That's when I'll apply penetrating oils and jellies and wait for what seems like forever to loosen parts (hopefully without breaking them) But... You can only do what you can do..Ho hum!