Having just done this, the biggest problem I ran into was coming up with suitable hold downs for the 2 6 volt golf cart batteries (you will NEVER regret doing that upgrade!!). My previous 12 volt "deep cycle" (ha!) was a maintenance free with a flat top that was held down with a steel plate across the top. The 6 volts don't have a clear shot across with the caps and the terminals in the way. My battery tray had a lip at the front and the piece below runs across the rear edge of the batteries and you need to run threaded rod on each side at a 45 angle down to the tray. Don't buy the "j-rods' they sell, they are too short (they expect a bracket the golf carts have). In my case the lip keeps the batteries from moving forward, the hold down prevents rear motion, and the threaded rods prevent sideways motion. Actually a much better solution than the original 12 volt hold down. If the batteries are in a difficult place to see the tops, get a battery watering kit. So much easier!
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