Reversing Gear Adjusting Collar rotating/adjusting tool? Screwdriver and hammer???

[mwh2319]

I need to rotate/adjust my Reversing Gear Adjusting Collar, but won’t rotate with medium force. Very tight. What tool or technique do I use? Have removed the Retaining Pin. I don’t want to just whack it with a screwdriver and hammer. Is there a special tool or technique for this?
Thanks

[Sam]

A couple yrs back mine was stuck on my early model A4. Never needed to adjust it anytime during last 40 yrs untill I noticed some forward slippage. Got it free by spraying it with PB Blaster penetrating oil. My problem turned out to be even simpler - loose "U" bolt on the outer sheath of the shift cable clamp. In the end I did not need the ring adjustment and for sure did not like the extra effort reguired to engage the detent with the shift handle.