rc - you might be missing proper battery cables, 6V really should have minimum 1 gauge, preferably 0 or 00 [commonly called 1/0 and 2/0] and the connections should be very clean and tight, preferably with good external toothed star washers, make particularly sure you have good grounds, battery to engine and engine to frame and cab
you'll find all of these old trucks lose the gas in the carb when left sitting, but it shouldn't be hard to start with the right technique, tap the pedal once, immediately pull the choke all the way out and hit the starter, with a good battery and cables it should start pretty quick, if you run the battery down cranking, there's something wrong! and of course you could give it a shot of gas directly down the carb after it's sat for more than a day or 2
wimpy cables [modern 12V sizes] and poor connections can be part of the dim light problem too, but there are also brighter bulbs available, and putting in Bosch relays for the headlights can help by providing a more direct path from battery to lights
Bill
