Frankensaw Chainsawmill 2.0
Later I rebuilt the sled with some straighter whitewood planks from ye olde local Home Depot, but kept all the pipes.
Simple lynch pins in pre-drilled holes set the height.
Caution on drilling your bar tip: I called the company and talked to one of their engineers and discussed the most Northward point I could safely drill a 1/4" hole and not compromise the integrity of the bar.
Using a ladder for the first pass gives you a straight and true flat surface for each following pass, and no need for any pesky rail systems.
It's a full on Citybilly set up, no safeties, no guards whatsoever. I do NOT recommend you build anything without guards and safeties, and PLEASE if you decide to sawmill, even with a bandmill wear chaps and other safety gear. Things go awry and wrong. Just because one crazy SOB has a gaggle of guardian angles on his shoulder doesn't mean anyone else can invoke them by copying designs.