First a little background. Finally after 3 years of a frame off resto, painting the 70 chevelle is in sight. While apart, using Dupont Nason (value line)Acrylic enamle,with hardener added, I have painted the inside of the front fenders,(fenders off) cowl and door hinge area, front and rear glass flanges. (glass out). Car is a shell completely stripped setting on the frame,doors and fenders back on. I have stripped the car of its origional and repaint coats to bare metal, and then applied DPLF epoxy primer, followed by body work, and then Dupont 131s fill and sand acrylic primer-surfacer. I have blocked 3-4 times with this primer. Car has been setting since last summer in this stage. I want to do a bc/cc job and will be doing it in my garage. (Yes I will be carefull), Been reading alot of posts on this, THANKS. I would like to use PPG if possable because I can get it at a reduced cost. Here's the questions I have. Should I apply a sealer over this 131 primer before topcoating? If so what do I use. What bc/cc system should I use? Should I stick with a Dupont system or can I go with PPG. How do I approach the issue of painting up to and in some places over the already painted Nason stuff? Not a show car but worth putting decent $ into the topcoat. Thanks alot for the help.

Any suggestions?