Andy,
Wait until you are trying to get parts for your V-8 TJ.
Parts person: What vehicle is this for? You: Speaking before thinking, 1997 Jeep Wrangler.
What engine? 5.2 V-8
Sorry sir that engine was never offered in your vehicle.
Or trying to get parts for the axles. The front is a HP44. Sorry but your vehicle was never offered with that style axle.
Stacey David makes a nice book for keeping track or parts & part numbers on project rigs.
[URL]https://www.staceydavid.store/products/project-planning-book[/URL]
I know many do a spread sheet on their computers but I still like my paper books for things like this. It's a lot easier to take this with me to the parts store.
My local NAPA knows me well enough now that when I come in for a part they ask if it's for the Jeep? If I say yes then they ask what the donor vehicle was for the part I'm looking for.