my dads demon went 10.70s wit a 1.45 60ft for almost 2 yrs on a stock /6 driveshaft with the small u-joints. I would just pick up a set of spicer solid body u-joints and go for it. your gonna need a shaft loop anyways.
Safety loop is already in. Yeah I know guys that beat the total crap out of the 7260 U Joints and they live all day long.
HOTMOPAR; You would be amazed how strong those baby joints are!! Because I am cheap I ran a stock shaft up until this winter along with the 8 3/4. Ran mid 9s on the bottle and a 6.0 @ 125 boosted and tire shakin 1/8th.. lol