WARNING Avoiding an altercation when replacing an Alternator on a 993 or 964

A remanufactured alternator.

I just ran across this and although I think it is a rare happening when installing a remanufactured alternator. However, the severity of the resulting damage, I feel, warrants publishing it here as an FYI for 993/964 owners.
Picture credits go to J. Cochran & Boxster-PTE members from Rennlist.

Apparently, some aftermarket remanufactured (reman) alternators use an improper wire mounting block. It allows the heavy hot wire to short to ground when the heat-shrink insulation on its wire terminal wears through from coming in contact with the metal alternator body. If you ever replace your alternator be sure the reman unit has the correct wire mounting block and all the insulating shrink-wraps on the terminations are in good shape. If not here is the potentially catastrophic damage to the engine wiring harness that will result in a very expensive electrical harness replacement. 

Also, keep in mind the most durable reman alternator with the correct mounting block is most likely made from the alternator removed from service in your specific car and taken to a local motor/alternator rebuilder.  At the rebuilder's shop, you can discuss the rebuild with a knowledgeable counterman and come up with a list of what internal components should be refreshed.

Burned wiring harness

Here is where the connection to the improper mounting block resulted in grounding and caused catastrophic damage to the engine wiring harness:

Abraded shrink-wrap terminal insulation

Below is the improper mounting block that leaves the circled part of the alternators casting exposed and able to come in contact with the hot wire providing the path to ground and shorting out the electrical cable

Incorrect mounting block

Below is the correct mounting block that includes an insulated wire guard that protects the connection from grounding out to the alternator body. One should check and verify the reman alternator one will be installing  has this guard on it:

Correct mounting block

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