Quarter panel removal?
Don't remove the 1/4 for that!!!!!
Go to your local paint supply store and ask for a gallon of GEM. Don't ask, just use it and you will be totally satisfied! I use it on everything! Use a squirt bottle and get busy. If you can't reach certain spots get a 360 nozzle for a cheap yard sprayer.
Here is a link to the stuff.
http://www.gemrustkiller.com/index.html
It really works! I had this stuff dripping out of every crack and crevise beneath my Cuda. I sprayed it all inside the 1/4's, roof rails, rockers, cowl and frame rails too. It runs around $18 a gallon.
http://www.gemrustkiller.com/index.html