$ .99 spray paint on the inside is fine.
It looks great just like painting r/c car bodies.
it'll have a high gloss look on the out side and won't matter if you just slapp
the paint on the inside with runs or what not.
just makesure you apply enough coats as someone metioned so you can't
see through.

just make mounting tabs for hold down screws.
or harden the wood mounting area with CA.

i don't trust the sealing tape.
you can leave the 1/4" or less un painted on the edges of the canapy if you want to
perminately glue it to the fuselage. use the sealing tape to conseal the marks.

glue on paint ? the paint will crack away from the canopy. during flight.lol