a 833 4 speed transmission with bell-housing

Nothing wrong with the input shaft, the taper is shorter , was done because some cranks weren't drilled deep enough. You can lop off an inch and still run a roller pilot bearing that sits into the register like a magnum.

The iron bell housing is and was not desirable, no one wants them...that was a research blunder on your part, you bought that junk on your own.

Now for a little inside info on what I see that trans having... a ring groove on the input means, if I remember right... low 1st gear "possibly od trans". Which way, up or down, the reverse tab points... is usually a dead giveaway of of trannys , if there are tabs that is.