Evaporust isn't supposed to removed paint, so apparently there wasn't much there that wasn't 'integrated' with the rust/dirt...
I don't think GM expected anything to be there after 44 yrs anyway..
If you leave a part in the solution for a minimal length of time it won't remove the paint. If you leave a part in the solution for two days, as mentioned about the driveshaft,the paint will become very soft and easily removed by wiping or brushing.
Guess it depends Jerry as I had soaked mine for two days but this is what I found after the first day of soaking. Guess some had seen what I used a couple years ago concerning the 4" PVC capped tube with two gallon of evaporust.
As anyone can imagine I was quite happy with what I found and it was not noticed before the cleaning. I should add I had the drive-shaft then completed by Quanta to remove the pits that were in the tube near the rear section and then duplicated the paint found on the yokes and drive-shaft.
the PCV 4" tube I made up and the first drive-shaft which was out of a 69 Camaro 307/automatic.
P.S. Thanks George.......