The Bullseye web site has virtually no info. Apparently they do not have kits for installing on specific chassis, just a collection of different length screwjacks and different size motors and its up to the owner to figure it out. No WAY!!! Given the very few different chassis' in the motorhome business, (really, think about it..... Ford E350/450 is by far the most) why would they not engineer custom install kits? if they want to sell the units?
Unless there is a manual crank on each screw, I would not want them. What happens when a wire breaks, motor burns up, etc? On hydraulic systems, you usually can cheat them by loosening a line and allowing fluid to leak out as the springs suck the actuators in, or as you use a jack to force them in. With mechanical screws, you will quite literally get the screwjack if it fails.
Merecedes is very peculiar about not drilling into or welding on their chassis. I'm willing to bet that other chassis mfg are the same way. The HWH system installs on the Sprinter without drilling a single hole in the chassis. It picks up existing holes and makes for a neat install.
Charles