[lithiumsupplement]

Update: I got all the parts I needed from AliExpress and overall the cart is running great. Climbs steep hills with the family aboard (not quickly but that's ok) and gets more miles between charges than I need, which is great for a battery with dead cells salvaged from another project. Now I'm trying to finish up the project so I'd love your help:

1) Lights not working: The cart has a positive wire that I hooked up to the 12V+ out of the DC reducer. I can't find a negative 12V wire to connect to the negative end of the reducer. Any ideas?

2) Likely related, but without connecting the DC reducer negative to anything, on only the positive wire, the break lights are on, the running lights are on, the horn and reverse alarm works, and the turning indicators light up but do not blink. Unfortunately the lights and beams do not work. I tested the bulbs directly on the 12V power and they do work, so they are not getting power from the cart.

3) The windshield is pretty scratched up after 35 years of use. Any ideas how where to find a replacement?

As always, your help is very much appreciated!