Quest for Stronger Rear Spindles

[Jagdpanzer]

Since I twisted off a rear spindle on my very first attempt at drag racing my Z a couple of weeks ago I have been looking into finding a more rugged solution to this obvious weak link component in the C4 drive train. In my search I’ve come across a pair of these custom made billet spindles specifically for C4 Corvettes. Unfortunately the seller has no knowledge about the original manufacturer however, he does claim though that they are machined from 4340 billet stock and much stronger than stock C4 spindles.
Has anyone here ever seen these spindles before and do you know the story behind them?