accessing control valve linkage

[wayne l b]

I have a JD 755 tractor with a series 70 loader and a Laurin series 755 cab with heater/ac . The linkage on the loader control valve which is under the seat is broken, Is there a way to get at the linkage without taking the cab off, I was thinking of cutting a work hatch in the plate steel in front off the seat, would i be able to get at the linkage from there. I have never seen what the valve looks like. The tractor was purchased with the cab on. If anyone can supply a photo of the valve and linkage and its general location under the seat then I can make a decision of where and if to cut the cab. Thanks Wayne.