OK, found my 4.10 pinion (tripping over the differential with ring gear next to it kinda helped), so here are the pics -first is the bar pinion, you'll notice the small radius/fillet where the shaft for the crush sleeve bore meets the perpendicular surface of the step for the crush sleeve face to rest against:
You must be registered for see images attach
And then here it is with the crush sleeve slid on backwards, this is as far as she'll go:
You must be registered for see images attach
Second pic shows the fillet better actually, but I left both of them raw so you can zoom in well. The reason why the crush sleeve is hung up there now is that upon crushing during installation its end facing the pinion outer bearing gets shrunk a tiny bit in diameter so it's very tight around the pinion shaft, while the other end (facing the pinion head) gets stretched a tiny bit to clear the fillet I mentioned. If I had slid the crush sleeve on the way it came out it will go in all the way, but I flipped it for the pics just to illustrate my point easier. A solid spacer cannot shrink and/or expand like the crush sleeve does tho, so the inner edge of its end that once installed will be facing the pinion head needs a slight chamfer to clear the fillet on the pinion, or the spacer will get hung up just like the crush sleeve did in my pic. Keep in mind that not all pinions are the same, this 4.10 in particular seems to have quite a bit smaller fillet than the 3.55 that I used the solid spacer on, this the spacers would have cleared the 4.10 fillet with about half the chamfering it took it to clear the 3.55 fillet.