That's about how we do ours: prep and paint, then roll the boat
back a foot and do the touch-ups. This works because we have rollers. If you have flat bunks, you're beat i think.
other suggestion is to buy/borrow some straps and hoist the boat
to get the missed parts
... if you have access to a crane, or a garage/barn with rafters strong enough for chain-lifts.
I've seen some folks who