No one makes an adjustable timing set that I am aware of, the offset key will be your most likely option to use. Mr. Gasket makes an offset keyway pack that can be used on most engines that use this method. You can explore their website, and see if the ones they offer use the same size keys as the 235/261 engine. If so, then thats all you need. Just put a degree wheel on the engine first to verify where the cam timing is to begin with, and then verify after you install the keyway to make sure you went the right direction. I have a degree wheel already mounted to a solid hub that will work for these engines, so let me know if you need to borrow one....
