That's not a problem. Just pick strings that will give you workable tension at this tuning.
There is a great online program for calculating string tension athttps://wahiduddin.net/calc/calc_guitar_string.htm
Just put in your scale length (25"), your desired tension (18~25 lbs?) and the note you want to tune to. The program will tell you what string diameter will work for you.
Do you need to taper the neck on a short scale, say 20 to 23 inches?
i'm sorry, a six string short scale.......
Hi, the reason for the taper is to make the instrument easier to play. Strings are closer one end for fingering ease, and wider at the other end for better space for picking.
Fingerstyle guitars often have a wider fingerboard and string spacing but still tapered.
if you feel comfortable playing with six strings with bridge end type spacing at the nut, go for it.
Pretty much any popular scale length will work? I’m guessing you’re probably using another guitar as a model? That’s usually the best pattern to follow, since you know the fret layout is correct? Here’s a link to a shorter 23” scale template if you’re feeling adventurous, it’s a good scale length for GDG tuning?
Here’s an idea of as what gauge of strings for a 3 string GDG tuning work the best:
cheers & good luck :)