That'll definitely help. The problem arises if you're going to have a vertical/horizontal, that now your foot is 8" off the ground, which pretty much negates any advantage to going vertical, you still have to lift the round, and will be bent over and akward lifting as well.
If you're going horizontal only, welding the wedge to the beam and having a moving push plate is simpler, and gives you the ability to just keep pushing the wood off the back of the machine as it's split, onto a conveyor if you're getting fancy. Adding a 4 way wedge is easier as well.
Just my thoughts. I'm on the lookout for a cheap H/V to use in the woods behind the ATV but the big splitter behind the tractor is horizontal only, and I like it that way.