https://www.ebay.com/itm/1968-68-MUSTANG-SHELBY-GT-350-SEQUENTIAL-TAILLIGHT-HARNESS-KIT-ORIGINAL-FOMOCO/362548176478?hash=item54698e265e:g:vh0AAOSwDEBcVgR8:rk:6:pf:0
I am flattered by the "cool directions". I think I made that crude drawing thirty years ago. LOL
Unfortunately, the only original parts are so butchered they are not useable. The rest is reproduction. I wonder if your customer knows you are trying to sell his parts? The good news here is they are garbage and they shouldn't get anything close to $650.
If you take car to someone have them give you back all the parts they removed from your car. If someone did this to me, it would be the last time.