Hey all I'm a new member

I've came across the site before and now I thought would be a good idea to join.
So anyway I just got a Yamaha TRBL005 (yeah I'm a lefty) and I converted my first bass (a cheap Stagg) to a fretless.
My 2nd bass (a Tobias standard) is the only one I dont use as much ever since I got my 5 string. I thought about tuning it up a fourth higher like good ole Stanley Clarke and Victor Wooten do
The only problem is I've heard storys of necks snapping because of the tension that can happen
anyone got any ideas how to reduce the tension for this type of tuning?
Regards-
Rick