My advice would be to get the Wittur SGV (AMD model similar). This is the same operator used by Vertical Express (TK), KONE, and Savaria. Both models are now available with an upgrade kit to work on exisiting MAC pickup rollers. The only think you will have to change is the operator, tracks on the cabin side , and the clutch. The operator is fully assembled and is a drop-in replacement. No need to redrill the doors. Just specify MAC adapters. The advantage of the clutch is that it comes with an interlock (not restrictor), eliminating the chances of door misalignment during runs (someone trying to pry doors open during run as a prank, or clipped rollers). to learn more about this product, please see my recent news thread on this same site titled "One size fits all Door operator". Link: http://www.vatortrader.com/forums/ubbthreads.php?ubb=showflat&Number=33378#Post33378

The Otis product is not your best bet in this case. Additional "homemade" hardware will be necessary to accommodate the MAC clutch.