I can't believe I missed your progress on the mammoth, particularly the lift cylinders. I'm working on a similar project and came to the conclusion to make double acting cylinders. Problem I found was like you said about having the holes in side of cylinders. I still have to tackle a cylinder head with both ports on it and tube inside first stage. Hade same thing with cylinders not coming down very well with reversing pump. But it is possible and in a couple months I'll not be able to put it off anymore
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