We have two different approaches.
For a slow build: We paint before pieces are riveted, yes we make sure the mil thickness between the parts is minimal. This makes all the rivets uncoated and polished. There are no dry lines, no runs (well not many anyway

) No over spray on wires and stuff. Looks really professional, like you thought before you acted.
Next: if we are doing a quick build results are not quite so good.
Get the cockpit parts fit,
Do not rivet down the seat back hinges
Get the front and rear skins fit, paint these separately
paint all the cockpit panels and parts separately
Fit the canopy rollover bar
fit the canopy rails
get the canopy frame to work perfectly (minus the slider latching mechanism)
Remove the canopy frame Paint this separately
Paint the cockpit
Now you can proceed with everything else, eventually you WILL run out of things to do and you WILL fly it.