I haven't done it but have the same problem you do. If you raise the wedge do you need to raise the cylinder so it is centered on the wedge. If it isn't centered will it put a bind on the wedge assembly as it slides. I know there is a lot of clearance, just wondered about that side of it. I have thought about putting a sacrificial block for the wedge to hit. My splitter stops 3-4 inches short of the anvil(?) and sometimes I think if it went that extra distance I would get a clean split. I go through about 6 cords a year and still need 1 1/2 to fill me up for this winter. I live on a small 6-8 acre wooded acreage and in 17 years have not had to cut down a live tree yet. Just keep cleaning up the standing dead wood.
Take Care,
Doug in SW IA