I feel like I wouldn't need markers, used to cello, I tuned my bass in 5ths like a cello.
Would be cool if I found a cello scale neck...
I don't know quite what to think about tuned in 5ths. There are a number of people here in TB who are into that but I've never tried it on a bass guitar. I went the other way with more strings. Note I do play 4 string tenor banjo so I am somewhat familiar with tuned in 5ths, and one thing I know it that it seems to involve a lot of stretching to reach things! On a bass that would seem to much worse than on a shorter scale banjo. A cello scale neck would be cool except that you might have to play it vertical like an electric upright bass.