I designed and manufactured a one=off bolt-in transit connect lowering kit. I am a mechanical engineer. The kit can be uninstalled and is completely reversible and rode awesome. It includes new front coil springs and a new rear suspension system. I have the engineering drawings for all the parts so these could be reproduced. It lowers the van 3+" in the rear and over an inch in the front. It is designed to level out the ride height while still being matched to the factory dampers and allowing some usability of the van (cargo capacity). $750 for the kit. $500 more for the engineering drawings. (This kit took many many hours to design and much more money to produce)