Dodge sportsman 77 vogue electrical help

y y'all I just traded my van for this sweet 77 dodge sportsman vogue. I can't figure out the electrical system. I have an extra deep cycle,and two terminals in the back of the tv for it to be hooked up to. I am mechanically inclined and have installed isolators and rewired accessories etc. just in the dark on this currently (literally). Is my voltage regulator out because my battery seems to be overcharging and hissing when plugged in which may not be causing it to full charge and not complete the circuit, which is not letting me get enough electricity for the lights? I want to figure out how to use my lights and water pump off of my deep cycle, not my starter, yet still charge them both when driving. Can I do that alone with original 77 vogue motor home set up? Also I do not have a generator.