[Hallicrafters] SX-71 - how to remove chassis crud??

[RJB]

Good morning folks,
I have just received a clean straight and working SX-71. This my first Halli
up close and personal, and i am pleasantly impressed with the build
quality - i had assumed it was a cost-cutter step down from the SX-62, but
in fact it has nice solid metal-work and neat wiring.

But like all ba's with mesh-type lids it has years of accumulated grime,
absolutely welded to the top of the chassis. This muck is only apparent up
close, at a distance it looks reasonably clean. My recent experience with an
NC-300 suggests that isopropyl alcohol is not very effective on this stuff.
Acetone will move it, but not *remove* it, the acetone evaporates so fast it
simply dumps the crud somewhere else.

I refuse to use abrasives to clean an old chassis, and the radio is too
complex to strip down to bare metal and put it through the dishwasher.

So... do any of you more experienced ba gurus have successful techniques for
crud-removal, or should i leave it as is?

thanks in advance
Bob Bennett, Maple Vly, WA