http://fingolfen.tripod.com/eseries/e50.html
I am planing on doing this build with the hl king tiger. I am starting with the running gear....the e50 suspension looked like this...




The E-50 hull was to be longer than the Panther, in fact it was practically identical to the King Tiger in overall dimensions except for the glacis plate layout. The hull of the replacement for the King Tiger, the E-75, was going to be almost identical to the E-50, except the armour would have been thicker. Two extra bogies, one each side, would have been fitted to compensate for the extra weight. The bogies were re-spaced as well giving the E-75 a track to ground contact length of 4095mm, compared to 3850mm for the E-50. The whole drive train would have been the same for E-50 and E-75. As they were both to be armed with the same gun, ammunition stowage and overall internal layout was to be identical.
here is a pic with the mybech motor in place...As mentioned earlier the final drive for the whole series was meant to be at the rear of the vehicle. However none of the drawings of E-50/75 make any space allowance at all for a rear gearbox and final drive except for adding teeth to what was the idler. For instance the turret would probably have to be a couple of feet further forward on the hull top. Also they all show the standard Tiger II sprocket at the front of the vehicle as well! I think that the E-50 probably had the gearbox at the front: the E- 100 certainly did.