Three heavyish coats of LM brushed on for me, and then let it dry naturally. I have sprayed it in the past, it's certainly quicker, goes on more evenly and uses less material - now I'm spraying more again I'm thinking about a small HPLV touch up gun for the mask to speed things up a bit lol.
You're shell looks great mate, I'd have been well chuffed if my first attempt came out like that! As for the paint lifting with the mask, assuming it's water based, my guess would be either grease on the shell, or paint going on too thick and not drying well enough. I always heat my shells slightly before laying down a lot of very thin coats, and using a hot hairdryer between coats to set them.
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