I realized I'd forgotten some mods in my original post so I thought I would add them here:
This drawer has a long full extension slide but a short drawer apparently to leave space behind for wiring and plumbing. But the space was much larger than necessary so I made a simple box and attached it to the back of the drawer to effectively make it bigger.
Made these levelers from an 8 foot 2X6. I cut it into four 2-foot pieces and glued them together face to face to make a 6"X2' block from which I cut the various pieces with a band saw. Whether you make or buy these, I highly recommend them because they make leveling so much easier.
These wheel chocks are easily made from 2X4 scraps and a threaded rod etc.