2. I would like to meausre amps but I am not sure how to do it when the battery is charged without heating up an blowing up my voltmeter
If you want to measure how many amps you battery is taking from the charger, run it inline and on the Amp setting on the Multimeter. If you want to measure from the batteries to the motor, just run it inline and rev, the motor will turn and it will give you an amp reading.
Be careful if it is fused though because Hot winds will pull over 10 amps at full throttle, even with no load.
I use one to check motor efficency, and whether my batteries are charged or not, also whether I need to turn the engine over on the car because the 12 volt is going flat. Jonathan