I managed to over-torque one of the bolts in my Trimetric's 500a shunt and it broke off. I drilled out the stump and now use the now shorter bolt in the threaded hole, but now I can't stack as many terminals with that bolt :( ( Ok I am a spaz)
Mex says not to stack at the battery post and I use the shunt as the neg bus, so I cleverly use the longer bolt as the "outer end bolt" and the now short one to take the single shunt to batt wire.
So the inner end shunt and the batt only has one ring terminal ( with a 12" #1 wire from shunt to batt.) If the longer bolt on the outer end of the shunt can't take any more stacked terminals, I create another bus that can take some more negs, and run that over to the shunt's outer.
It's horrible to look at but it works great! :)