70-71 340 unsilenced air cleaner finish question

I would think that anything that shows on the outside would be wrinkle finish. That is the way I've always done them. On the inside of the air cleaner and lid, and also under where the pie tin rides....I use PPG DP90LF epoxy primer. It dries a semi gloss black, and holds up well. On the wrinkle, I have used both the VHT, and Harley Davidson side cover wrinkle finish black.