On Sunday, November 22, 2020 at 9:01:16 AM UTC-8, Richard Pfiffner wrote:
I built one of Jay's jacks many years ago with his parts list, pictures and prints.

It works great and is very robust.

Richard
www.craggyaero.com

If you need more clearance in the lowered position a double-acting bottle jack is the answer:
https://www.northerntool.com/shop/to...E&gclsrc=aw.ds

Tom