Thanks Arkay!
In my snooping around the internet looking for build ideas, I came across quite a few home brew single string instruments like Diddly Bows or more of a upright bass like you are thinking of building. Plucked or slide, it's surprising how versatile many of these are and there and have watched several YouTube videos that prove that out.
Good luck, and make sure to post some pics of it when you get it done :yes:
RC
Reminds me of some interesting "prison guitars" I've seen. Very, very, cool, and if that amp ever needs work send it my way.