I removed the now useless 2nd bottom bracket and drilled holes in front of the rear wheel in the triangle for an aluminum tube. The aluminum tube is super lightweight and should work just fine as a foot peg.
Best upgrade so far: I fixed up the driver’s seat. I used two L shaped pieces of pipe, attached the back rest at lumbar height with a 1/4″ bolt and large washers, then attached a padded seat to the bottom by using a piece of pallette wood. The real bastard was attaching the seat to the frame. This I accomplished by welding two tabs onto the frame that fit between the two L shaped pipes that are the frame for the seat. I welded 3 small pieces of 1/4″ steel plate together and drilled a 3/8″ hole through them to make the tabs. I then drilled 3/8″ holes in the two L shaped pieces of pipe and stuck bolts through. 1/4″ is not enough! I tried and the bolts simply bent and had to be removed with the Dremel.
I placed a large exercise machine seat for the rear passenger. To give them something to hang on to, I welded some kids bike handlebars (the type with a big U shape to them) onto a seat clamp, which I then clamped onto the original seatpost.
I added under seat steering. Tom Kabat of Woodenbikes.com had this on some of his bikes and it is super comfy. I cut some kids handlebars in half and welded a 90 degree angle in between. Tom bent some pipe into a large U shape, which would be preferable, except that I can’t bend pipes (yet). I think a V shape would be ideal. Basically, with a SWB layout, the steering tube is just a little bit forward of where it would ideally be. You can put above seat steering but it has to be high up to not interfere with your legs (if you use standard handlebars). With under seat steering, the handlebars have to come back far enough to reach your hands and have to avoid interfering with your legs when you are stopped but at the same time the closer in to the frame you bring the bars, the less you can turn the front wheel at low speed (because your hands hit against the frame).
Unfortunately the Kollmorgen’s hall sensor board did not like me resoldering the wires (which were flimsy after all the work done around the motor)! Two of the traces flaked off. I had to Dremel around the board to remove it and try some surgery. So far, the fix is not working, but I’ll give it one more shot before swapping motors. Never again will I buy these sensored BLDC motors/controllers! So much trouble for too little gain.