I am going to get a clear bra installed on my E46 M3. I want to make sure that I get all the wax off the car and clay bar the front bumper so that the 3M film will adhere to the paint.

Is there something I can use to really clean the paint before clay barring and then washing one last time? I dont know about using Dawn, and somone recommended some 3M Wax Remover solvent? Anyone used this?

clay will remove the wax, and all traces of it. I don't think you need to do any of those other steps.

After you clay, do a wipe down with prepsol or similar paint prep product. That will remove ALL traces of wax. You can also use isopropyl alcohol (rubbing alcohol) in a pinch.

...or vinegar