If you boat in salt water, you should paint your tabs. many paints will nit stick well to stainless steel. In addition applying copper based bottom paint to bare stainless is nit advised.
The tabs need to be clean ( sanded or scrubbed to the metal) using a primer designed for metal. There are a few option, Interlux Primocon being one.
You can also use Trilux 33 as a primer, followed by regular bottom paint. I have had terrible results using Interlux33 by itself as an antifouling treatment for outdrives. There are also two part etching primers for stainless but I can't remember the name that was recommended for tabs.
Although non copper based antifouling paint like Pettit Hydrocoat ECO may work, I have no experience using it on bare metal.
Befor you go nuts, check with other boaters in your boating are to see what they do for their tabs. Many don't paint tabs at all.
With respect to the hinges, they are originally made and still are made by Southco. There are several options, the main one being the angle where the door snaps into a detent, keeping it from flopping up and down. A common option is 120 degrees for helm electronic boxes and 90 degrees for overhear boxes (since 90 degrees is just about as far as the door cab rotate before it hits he bottom of the hardtop)
Your hinge is probably one of the hinges shown here:
C6 / G6 - Detent Hinges allows users to easily position doors or lids and hold them securely at pre-determined angles
southco.com