Here's a couple pictures of a conversion from 4-string to 5-string.
I added a piece of aluminum angle to the side of the neck, and modified a spring clothespin to be a sliding capo.

And I installed a guitar tuner down near the tailpiece.
It sounds as good and LOUD as ever. And, if anybody wants to restore it to original 4-string status, there's no 3/8 inch hole in the
side of the neck.
It's for sale. $165 plus shipping.
Pardon the BLUR,
but I'm new at
digital
shootography!
There's alittle wooden block that
supports the barrel of the peg. And the
plate of the peg is fastened to the
tailpiece
If you are modifying a 4-string, please
NOTE! Fastening to the tailpiece only
worked on THIS banjo because of the
unique shape of the tailpiece. Your
banjo may vary. (And I'd be darn
surprised if it didn't.)
$165
plus shipping
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