I am a newbe here, looking to purchase a classic datsun truck, 1960's era, I am currltly looking at a 66 truck and a 64 unibody truck, going to convert it to electric power, need to know the carrying weight stock these trucks would carry, when converting to electric, battery weight is a issue, batteries alone can weight up to 1200 lbs for 6 volt and 600 lbs for 12 volt system, also do they sell disc brake conversion for these trucks.