ABS system fried, 1995 Cadillac Sedan Seville SLS Northstar

A local mechanic got a part from Houston to replace the ABS system which is fried. but he told me part of it was missing, so what part might that be?

Is he talking about the wiring harness? or something altogether different?

Sorry to be so glib, but “a part” is not enough info to even attempt an answer. You might as well just say “I bought a part for my car, could you tell me where to install it”?
This really needs to go here:

Houston, we have a problem.

Suggestion: ask the mechanic which part is missing. How would we know which part is missing?

Is this a riddle?

How many guesses do we get?

Is it bigger than a breadbox?

If the part were an animal, what animal would it be?

We need more info, lookat. No crystal balls here today! No offense, it’s just that your description of the problem isn’t specific enough.