Well Don't know how much I can help, my lid is a bit off too, on the drivers side I made the depth of the well to small(shallow) , but I really messed up that lid with heat when I tried to shrink it, till I get the latch & rubber bumpers on I won't know how much work is left.
I would think you can do the skins later, seal up all thats going to be hidden behind them. As for the shell, I would try & prime as much as possible, use the inhibitor on the areas that you still have to work. I know it's a waste of expensive paint but I might even shoot it all & then just wire wheel the areas to be welded later.
I've done a lotta stuff more than once,workin at home,with limited time you hafta do small areas, the hours fly by so fast you never seem to be able to finish what you start in one day, so I always have to improvise & touch up, even screwed up that nice hood patch I made, when I took the skin off today I saw a tiny line from the back, went to weld a few spots over it & blew right through, so now I have to do that over!
Always a challenge, nothin on this car ever went easy! Rich.