Casey,
You can apply decals on top of one another without having to add a second gloss coat if you wish I have doen it many times without a problem.
I recently did it on a A5M2a Claude that I built in 1/72 scale, three of the decals were two parts first was a silver rectangle and the second was Kanji lettering that had to sit on top of the silver rectangles. I gave the model a gloss coat and applied Micro-Set and the first decals, let them dry a bit while working on other decals than I came back and added the second set and some Micro-Sol. Both decals snuggled down really good. Once done I just applied a flat coat to seal the whole thing up.
The problem I found with adding a second coat of gloss before adding the second set of decals is it might build up the surfaces and you will not get a good look when trying to get the decal to snuggle down.
HTH
Cheers
Thom
IPMS Member #42958 / AMPS Member #2091
IPMS Central Connecticut (President)
IPMS Northeast Military Modelers Association (Web Master)
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