I just contacted Brookville and for any of you that are doing a '28 - '32, this is the information that I got:

"THE PRIMER THAT WE USE IS WESTERN SELECT ACRYLIC PRIMER RED OXIDE RS4201, THE LACQUOR THINNER WE USE IS 5770, WE RECOMMEND YOU CLEAN OFF AS MUCH AS POSSIBLE , THE METAL HAS NOT BEEN PREPPED."