if you use adhesive make sure it doesn't show........
You got that right!
Silicone, adhesives, coatings, etc are a big no-no. For a while, guys were layering vaseline up behind the plates to "ramp" the transition area through the center of the plate. You'd be surprised what the creative development department comes up with to circumvent the rules.
No adhesive necessary...stick the bolts through the carb, gaskets and plate, then bolt it up to the block. It helps if you leave the lower tank mounting bolt in a thread or two.