I gather you are curving these in one plane only and not attempting to create an M5 clone. (M5 seats look like the inside of half a banana peel) 3 ply veneer is probably too thick to bend much, so I imagine something resembling a lawn chair. Do you plan to use a vinyl airbag to compress the veneer or an external caul and clamps? Contact will work but not be anywhere near as strong as epoxy. Check out West System (Gougeon Brothers) for example epoxy glues for veneer. If cost is a concern, epoxy may be a nonstarter however. Contact might work for a trial effort and proof of concept. Steve