Thanks Jim, very helpful information. I did notice that the two doors that I buffed, the second one was much harder to buff out, must be due to the fact that I tried to use the same piece of 3000 trizact on it. I also bought a box of Norton, so I'll try that next. The 3m perfect it purple bottle, do you mean the bottles labeled 1-3? Do you use all 3? What do you use for buffing pads? I'm using wool, followed by black foam, both by Meguiares. My buffer is a variable speed Dewalt rotary buffer, works well, but is kind of a back breaker after a few panels. I'm thinking of maybe a Flex rotary?...what do you use? Thanks again Jim! Dan.