Personally, I wouldn’t do it; but I can offer the following. First do a google search for {"scale length" guitar} which will turn up a bit of reading including the following link. http://www.guitartips.addr.com/tip170.html I would put it this way: The 12th fret is theoretically half way between the nut and saddle. In practice the distance from 12th fret to saddle is slightly longer, because a little extra tension is put into the string by being pushed down onto the fret. If the scale length of a guitar is being increased by 3/4" the 12th fret will move about 3/8 " away from the bridge saddle. Dividing the longer sacale by the shoreter, we get 1.03, so it’s like we are scaling up the whole guitar by 3% Why have a longer scale? The distance between frets will be slightly greater, which may help if you do lots of playing past the 12th fret, or if you have big hands. Obviously the width and taper of the neck can also vary. Using the same guage of strings will obviously result in a higher tension, since the same note is to be attained from a longer string.