I've got the first reverse grunch thing going on real bad. Gets worse as tranny warms up. 901 with side shift that shifts pretty well otherwise.

What can I do to improve??

Can we assume your clutch is adjusted properly?

Reverse should never crunch if clutch fully disengages. Unless it is crunching when you let off the clutch, then check external adjustments.

Clutch seems to be adjusted ok. Pedal has freeplay. I can go into second freely at rest.

But if reverse can not grunch then it must be clutch drag because reverse crunches same as first.

Everything else shifts fine

I'll double check clutch adjustment

Yup. Clutch too loose, could be stretching cable.

Why does reverse crunch? It does so because it is a straight cut gear that does not have any provisions for synchronizing with a moving slider. This, if there is any movement in the transmission input shaft, it will be communicated to the reverse bits and you will get grinding while trying to select reverse. Reverse will not grind unless it is moving. It wont move unless the clutch is putting power into the gear box.

Have you checked to see if your clutch tube is still welded to the tunnel?

Adjusted a bunch of free play out of the cable. Seems better. No time for a full test drive. Will do that tomorrow and check the clutch tube too. Thanks guys.