Steve...on a personal note........damn you're old!!!!! You were using heet before I was born!
Here's an exerpt from the Heet MSDS:
Incompatibilities with Other Materials:
Strong oxidizing agents, aluminum, zinc, or metals that displace
hydrogen,
rubber
and rubber based coatings, chromic anhydride, lead perchlorate and
perchloric acids.
Its basically just methanol...actually a mix of 99% methanol and 1% of their "proprietary additive"