ball diff broken

[racer11]

after 5 rounds of 5 minuit racing spaced 15 minuits apart the ball diff in my 22 gave in, (while trying to tighten it by holding wheel and spur and turning bolt in the ball diff the bolt just spun instead of being tight) i had tightened the diff two meetings ago and wondering if that could have caused it and how could i fix it. would this work;

http://www.apexmodels.com/gbu0-prodshow/TLR232001.html

or is there a cheaper quicker option than to take apart and rebuild the diff.