Hi Pat and
to the forum.
The alloy rim should work fine with caliper or "V" brakes as long as the pads can be adjusted for the 25mm wide rim.
No specific adapter is available to mount the 36V 12 AH battery LiFePo4 on the bottle mounts. The battery is probably too large for most frames and too heavy to be supported by just two bottle mounting rivnuts.
The following photo shows how one forum member mounted his battery, but one of the bottle mountings eventually sheared off due to the excessive load:
If you have room within the frame triangle, you might be able to make up a strong bag or straps using seat belt material to hang it from the top tube
(cross bar) of the frame.
A 36V throttle will work with a 48V battery, but I recommend that you disconnect the supply to the throttle mounted battery gauge, and either leave it disconnected, or fit a suitable resistor inline to prevent it from getting too hot.
It appears that they are using the same group of photos for both the front and rear motors.
Alan