I need to make some burgundy gelcoat.

I can start with neutral gelcoat at $48.00 / gallon and add pigments
to get exactly the color I want.

I can buy it already colored to a match, but it's $200.00 / gallon.

Other than using 4oz / gallon of pigment to color the gelcoat, what
else do I need to do?

I heard of a pull test. It ensures no transparency at 18 mils dry film
and also ensures it will cure with that much pigment in it.
What is a pull test? How do you do it?

What do I need to do to ensure the gelcoat will cure properly and
cover without being translucent?

I have waxed two pieces of glass, about 3 x 5" and placed tape buildup
along two edges to give me .018" separation. I plan to catalyze a
little gelcoat and let it kick between the glass to check if for
transparency and also make sure it gets hard. Any thoughts?