'63 wiper motor question

[AdvancedAutoCC]

Hello all...
New to posting here, tho I've been lurking for awhile, and I had a question for the midyear gurus...

I'm working on a '63, and am having trouble with the wiper motor burning up the ground wires in the engine harness. This is the second "restored" motor (from an unnamed Florida supplier), and my question is:

Where exactly does the flat ribbon type strap go to (the one that comes out from behind the washer pump), and exactly how many grounds are there for the engine harness?

I understand that grounds are a major issue with the midyears, and I want to get this ironed out, naturally. I'm much more familiar with the C4 platform (took all of the training available for them back when I was a dealer tech in the '90's), and while I understand the simplicity of the earlier platforms, sometimes GM's logic leaves a bit to be desired.
Here's the history:
The original problem was non-functional wipers (the customer bought this from one of those "musclecar" lots, and some of that shows especially in the electrics), with a dead wiper motor and NO washer pump. I replaced the motor with a "restored" motor, as well as procuring a washer pump/cover assembly. I swapped out the motor and tested its operation, which was fine. I shut off the wipers in mid-stroke (to replace the blades), and when I turned the key back on, the ground wire smoked VERY badly and of course the motor was inoperative. I got another motor, and made a replacement ground wire, grounding directly to the engine. Everything worked alright each time I tested it, but of course..once the customer had it, the same thing happened. I checked the linkage for any binding (none), and knowing that components simply don't fail twice in the same manner unless there is a specific cause, I'd like to find out how to NOT destroy the replacement wiring harness I've now ordered for this car. Any help would be much appreciated!

[AdvancedAutoCC]

bump

[jerrybramlett]

There is too much to type in detail, so here's a summary. You can call me at (251) 478-4003 during Central Time business hours if you want to talk more. I think you've gotten two bad "rebuilt" WW motors.

There are several other visible ground connections in the forward wiring harness for a '63 (such as to one starter bolt, both headlight motors, the radiator core support, the heater motor, and the alternator housing), but there's just one that plugs onto the wiper motor metal spade using a plastic connector. The metal strap that comes from inside the motor goes to one (of the four) wiper motor mechanism cover screws. Actually, the wiper motor internals are wired hot all the time and the dash control switch makes a ground to turn the motor on. Inside the wiper motor is a Rube Goldberg system of coils, rods, and points to make everything work in the right sequence. This complicated mess is described in detail in the '63 Corvette Service Manual.