What's broke?

Ok here are some pointers from a guy who has been running A833s almost continuously since 1970.
1) you do not need an arbor, to hold the needle-rollers in place during a rebuild; just use a light grease; not Vaseline which at room temperature is barely grease. It is called jelly for a reason.
2) I used to use 100% Dextron-II cuz it makes for a superfast-shifting trans. however, it does not provide enough protection to the cluster pin, and you have to remove, and rotate the pin every few years, and cut a new slot for the woodruff key. So, I took the trans apart and modified the cones to shed oil faster, then switched to 50% 75W90 GL-5 gear oil. Now my cluster pins last for many years.
3) if you install full synthetic oil, be prepared to flush it out. I could not make it work no-how; At rpm it was just too slippery, and the synchros could not do their jobs. I had the trans down FOUR times in two weeks trying to make thatchit work. As soon as I went back to 50/50 it shifted like lightning, so to all you naysayers out there, yes, full-synthetic works... if you shift like a grandma.
BTW
My record to drop the trans, with the car on a 4-post hoist, with the GVod still attached, is 17 minutes, Yes I had a helper on one end, when it came time to dropping it.
4) I used to be a transmission rebuilder. As far as 4-speeds go, rebuilding the A833 is about a easy as it gets; with the Saginaw a strong competor.
5) IDK what your noise is.
By your description, it should be the front bearing. But if it was, the evidence would be in the oil. If the noise goes away in DIRECT gear while cruising, that would again point to the Front bearing.
I guess we'll see.