A833 od 4 speed abuse

Hang on man
I beat the crap out of that od box, with a very stout 400hp 367, never holding back, with an aluminum case even;

For street use, the only weak part in that box,
IMO,
is the M/S overdrive gear because of the very small contact patch between it and the cluster teeth. I broke a few of those, simply by forgetting she was a 3+1; and going into od with a bit too much gusto..... lol.
Well, I suppose the short-tail 904-sized M/S could also be a weak link, but you don't have to run it, that was a slanty shaft.

"They" say the Alloy case has a tendency to waller out the front cluster-pin hole. Well my od gear never lasted long enough to find out. lol. But eventually, cause I was piling up spare alloy boxes, I took one of them to a machine shop and had them install a steel front pin carrier, just in case "they" were right.
After four or five years, I switched to a Commando gear set, and installed it into a Passon alloy box, just because. I still have the bushed alloy box with an OD gearset in it, gathering dust on the shelf, with so many other, also-rans.