OK Tim. Good questions, good analysis and good comment.
My take.
1. On our older trucks there are no OE or OEM parts available except NOS and donor/rebuilt.
2. No "genuine" GM replacement parts. See no. 1.
3. The OE's supply is gone and the OEM's are now aftermarket Chinese companies making clones.
4. Not withstanding concourse vehicles/hard core purists, it's a little ridiculous to try and get exact parts that are unseen or unsafe. I.E. sometimes to get a OEM style tire, you sacrifice ride and handling.
5. Many parts supplied when OEM was available were changed in appearance and/or function anyway. Several iterations/revisions were supplied back in the day.
6. The aftermarket has tried to copy things as best cost/qty would allow.
7. If I buy from our vendors and the parts look the same or near, I call my truck original. I like to also get donor parts that are not of a perishable type. I enjoy using original hardware again and refurbishing anything I can. Do we expect to use the old wiring? weatherstrip? tires? rubber fuel lines? brake lines? horse hair? The people who say "it's only original once" are just silly. We all work pretty hard to bring it back to original and don't like that phrase. We restore them to original, but safe and reliable, as possible.
The truth is it's only "new" once.
OE= Original equipment on the vehicle when sold and over the counter parts at dealer.
OEM= Most of the OE parts were made for the auto mfg by subsidiaries and licensed companies (OEM's) Many are out of business or have been sold several times, changed names and changed countries.
