Interesting question.
Having built 2 explorers, one set neck and the other bolt on, it is easier to finish as much as possible before setting the neck. Once set it is such an awkward shape to handle which adds to the degree of difficulty.
Adding finish after gluing neck will help to fill the joint. From memory i think about 75% of the finish was done on neck & body then final 25% on the whole guitar.
Hope this helps in some way.
Cheers Waz
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