Lifter Rover/Mobile Gantry Crane

[gary.townsend]

I'm trying to create a way to make a modular planetary bases, 'm using a combination of HOME, KW, Nova, KAS, and B9 my original plan was to build a mobile gantry crane that could pick up modules with KAS and move them around, but i'm having to make the crane ridiculously tall in order to move the modules aroundand not having much luck launching the crane with any sort of success.

Then I seen a posting where someone was using a crawler type lifter, I've tried to duplicate that kind of lifter but i'm not having much luck my lifter scoots out from underneath the modules as the legs are retracting and it never seems to be able to lock docking ports. I'm wndering if anyone who has tried either of these approaches can offer some advice.