Incandescent/halogen lights don't mind which way the polarity is, LED lights
do, but as far as I know nearly all are protected.
do mind, and will fry, if they were switched on. If they were 'off', they should be OK.
At the same token lots of electronic gear
is protected anyway, if so: no problem for you.
I would check all items one by one, check all fuses
BTW, standard fuses would not likely protect the electronics from frying, the damage would have been done before the fuse 'melts'. It would protect your wiring
if correctly sized.
and drinking may not be a good combination. I have three suggestions:
* reduce alcohol intake (making an assumption here
* connect wires permanently to batteries
and use the switch to activate the circuits
* if the above is not possible and if you want to protect some gear
"reverse polarity protection", click on images
, and you will find hundreds of diagrams, the simplest is the bridge rectifier (4 diodes in one package) that allows operation regardless of polarity, but drops the voltage by ~0.7 Volt, or a Mosfet without voltage drop.