A possible solution would be to utilize a helical focusing mount combined with threaded lens cones to ensure that the lens and film stages are always in perfect alignment. From there, just add X- and Y-axis adjustments to the entire head assembly so that it could be aligned to the baseboard. Slap on a VC LED hybrid light source and mount the whole head to a strong column with geared height adjustment, brace it to the wall, and call it a day. Ideal construction would be a lightweight head and a rigid column attached to an MDF or ABS baseboard (for dimensional stability and precision of machining) to reduce pendulum vibration as much as possible.
Or can't someone please just make a new Graflarger back with LED's?