I have a first gen FJ40 Aqualu tub that the prior owner put in big tail lights that made it look like a Jeep. I took them out, welded up the hole, and now need to bondo them flat, anticipating painting them soon after. I understand that to do aluminum, you want to acid etch the aluminum, but not the bondo. What is a good method to do this? Should I go ahead and etch, 2 part epoxy, then bondo, then high build primer and finally paint? All within the open days of the epoxy?