833 OD sticking in 4th, chipped synchro

I saw that wear and dismissed it on account of I have seen a lot worse wear and the trans still always worked nice. The struts in my trans, have over 250,000 miles on them and still work flawlessly;......... and I have repointed BOTH the slider and the clutch teeth several times.i.
Since you have it all apart now, grab the slider and a strut, and lay it into the notch and make sure it fits into it properly and lays flat in it.
The sliders from the old style synchros will fit on the late style hubs with the late-style struts; but the new-style struts do not fit properly into the old-style sliders; they had different strut grooves.

IMO, the struts are not your problem, for me, the over-shifting is still on the table. When the slider is properly located and working in it's proper range, the struts never come out from under the slider, that far.
Try this; If you have an old 3-4 slider, lay it flat on the table beside the new one, and compare it's overall height which should be the same. Also compare where the fork-tracks are; flipping one of them over; making sure it is still in the same relative location. If you don't have an old 3-4slider, I think the fork tracks of the 1-2 slider are in the same location, not 100% sure..
BTW if the energizer springs are weak, this will allow the spinning slider to walk to the extent of it's travel, which, if the fork and or slider are worn, is considerably more than the design-travel, allowing the strut to pop-up on the trailing side.
I'm not convinced yet, that the fork is not bent.
>I would lay the fork on an elevated block, on the table, that only touches the rubbing surface of the pads on the fork, then measure the distance from the table to the upper edge of the pivot-pin, as far from the root as is possible. Then flip the fork over and measure again. The two measurements should be very similar.
>At the "bump part",compare the wear on the 3-4 struts to the wear on the 1-2 struts.
>Then compare the rub-bars on the ends where they push against the brass.
>You never came back with the dimension of the outter snapring thickness of the Front 307 bearing.
>Measure the depth of the rear bearing cavity, and compare it to the width of the 308 bearing.
The bearing should just fit in there, with little or no slop.
> Try to measure the distance between the clutch teeth of the first and Second gears. You may have to remove the slider. Then do the same between the Fourth and the Input gear again without the slider. Theoretically, these two dimensions should be very similar. Realistically the front is always baggier. This area is always the problem area.
Since the struts are all the same length, if the wear on the Direct-brass gets to be excessive, this allows the struts, especially with weak energizer springs, to walk out of the back-side of the slider, when selecting Third or Overdrive. I have taken apart transmissions where someone has installed an extra energizer on the Third/Overdrive side, in an attempt to limit the forward travel of the struts. I have never tried it so don't know how effective that might be and/or what the consequences might be to the shift into Direct.
>BTW; A230 struts IIRC fit into those late-style sliders. But as I recall are not compatible with the A833 struts. I forget why I nixed that swap, but I did check it out ...........about 50 years ago. So make sure your struts are all the same.