need more info what gauges?
If you don't disconnect the battery when installing gauges, it is possible to create a short circuit and blow a fuse. Some gauges have power present even when the ignition switch is turned off.
have you checked the battery output? it should show right at 13.4 volts, if not, check your alternator output.
they dont work
u dont
make sure positive cable is connected to positive post on battery. negative cable connected to negative post on battery.
yes if they are in a public place but if not then they dont have to be
yes lol theu dont change thereself
check fuses with test light under dash
Probably a fuse or a loose cable. Try that first.
old beetles dont use coolant
Water should be fine, but mix it with coolant when you can to prevent rust from developing in the radiator.
did you ever find out if this is possible??? I really want to do this also! Sorry I dont have the answer for you but if I ever find out I'll post on here again.