got and talked to him. gave me some great advice on how to handle the problem areas so going to try those tips and see what happens. he was great to talk to and very helpful.
thanks

Ive had the same experience on those old hand hammered alum car bodies.
I use 2% lanthanated tungsten ( Blue ) sharpened to a point , like everyone else said 1/16 diameter , small filler wire .035 .
I would also use 1100 rod if you can get it , if not use 4043 , those old car bodies were dead soft alum , nothing special.
Turn your ballance way to the cleaning side. If you have adjustable wave form I use sawtooth . Frequency real low 30ish , will spread the arc some.
Use scotchbrite on your weld area and your filler material. You can slip a piece of Copper sheet under your weld for a back up. Alum wont stick
to the copper. If its paper thin , you just have to let it roll up till it sthick enough for filler metal .
Absolutley the best way is gas welding , it takes along time to learn , but thats how those old cars were built.

just an update, thanks for all the tips, made some changes and seems to be going good other than the paper thin spots that show up. annealed the worst areas and they are smoothing out much better so it was work harden pretty bad in the areas that have been hammered on from all the wrecks. seems to be no end to the holes and cracks in the worst areas but gaining on it. the real fun was that when the FIA flares were added back in the 80's they put the right rear on one inch forward of the left rear so I cut the entire flare off and moved it back to where it is supposed to be. she's only worth a couple million be hey it's not mine so full steam ahead.
thanks again for all the tips.

here are a couple pics of the repairs as they are progressing

https://cimg4.ibsrv.net/gimg/www.off...b3a57d5793.jpg
https://cimg8.ibsrv.net/gimg/www.off...8d85584e66.jpg
https://cimg9.ibsrv.net/gimg/www.off...0d1ab7f164.jpg