I need to take the battery and shelf it sits on out to access one of 2 bolts in order to remove an upper control arm. Can I hook a set of booster cables from a spare battery to the battery cable terminals in car before remove it from car? I'm thinking this way power supply would not be interupted to radio, I would make sure the cables do not contact each other while doing this. My concern is would having 2 batteries hooked up to my vehicle momentarly cause a problem to any of the electrics because there would be too much voltage. I would of course have ignition off and key out.
thanks for any advice.