I saw a used 9.75 on ebay...it was going for $25 or something...

 

The IRS is a one off.Ibought if from an member on the boards years ago.Lightning preformance?Forgot now.He could not make it work.So I spent the last 3 years refining it to were it is now.almost 3 inches widers better camber curves and setting lower in the truck along withgetting the axles to run straighter for reduce drag.and I modified a locker to fit in the case.As for a truck falling off sure my design will run in excess of 7 g's.Plsu it is for road racing and track events would never stand up to drags.Stan