[Sparky dave]

Yes sounds like your on the right path. The traditional way was to apply body filler direct to metal but that was before the days of epoxy primer. Then 3 coats of 2 k filler primer. Then block sand with about 220 paper then most likely you will still have low spots so another couple of coats of 2k filler primer and block sand again with 320 then block sand again with 400 for solid colours or 600 for metallics, clean clean and more clean with panel wipe and your good to go. Use gloves so you don’t put finger grease on your primer. Good luck take your time don’t skip steps and it will look great