Hi Gordo,
The front of the RR frame is the same width as the Series but the rear is not. I kind of cheated a little mounting the rear crossmember. I cut the boxes that mounted to the Series off flush with the crossmember. In one of the first photos of the rear you can see the battery box/rear shield. If you look closely you can see the stainless steel through the PTO hole. I built the battery box to fit between the frame with the rear wide enough to reach the outside of both sides. The box is welded to the frame and the box is welded to the rear crossmember making the unit strong.
I cut 16" out of the center of the frame and a good section off the rear of the RR frame. I'm not sure how much but I guess if I knew how long a RR frame is I could figure it out. There isn't much overhang in the rear, and five or six inches less than the Series
$400 is a big chunk towards new brakes or a locker! You can make the one you have work. It could be mounted with angle iron or bent sheet steel for brackets.
I'm posting a few more of the rear but I'll see if I can get a few of the under side of the rear in the next few days.
Paul
The wheel wells have been trimmed since this photo but need more trimming.
