I have a Mares Ice Reg w/Yoke, I purchased a Din valve to be able to use my 120 hp. Does any one know what size the nut is on the yoke to take it off, I tried up to a 7/8 and a 24mm, the largest I have. I do not want to buy the wrong size wrench so I am wondering if anyone knows what size I need. Is there a smaller wrench that is made to do this job that I can leave in the Gear bag?