I have used L & M Stripping 14232 Aetna in the SF Valley , there's another one down on Alemeda in South Central L.A. , I don't know the name but one of my rich buddies swears by it and they did his '55 SD doors nice and leave a nice red oxide primer behind to boot - they did a good job on my AD sidemount fender - showed all the lace rust in the bottom edges of it
I'm sure there will be more metal strippers in the Long Beach or City Of Industry areas , time to crack a 'phone book .
Metal stripping is very good but can be problematic too : some years ago we did a V.W. typ III body and the chemical residue didn't get washed out of the ' C ' pillar , I have heard of this in the ' A ' pillar of pickup cabs too ~ any
part of the body that is built up will need carefull cleaning and rust proofing ar the rust will come back fast .