larger cylinders might work, but I question if a K has enough rear axle weight to carry that head safely. I have an A438 on a K2 and have the rear end loaded with wieghts. It is still spooky light on tail.
sounds like you need 2-1_4" dia lift cylinders if your hyd pump-relief valve will pump 2000 lbs(deadhead gauge in lift hose)and pull lever to read pressure. also keep header as close to throat as possible. used cylinders off f or g's should be the right length.
Thanks for the info guys!! I put a new pressure relief valve in the pump and now it works great! I already have wheel weights on the rear and fluid in the rear tires. Seems to handle it without much effort now. Thanks again!!!