I have a number of good 40A relays that I'd like to use on a lighting
project. How many H2 bulbs would it be safe to power a pair of H2 bulbs?

What wire size should provide power to the relays from the batteries using
a single relay? What about two?

Would the wiring from the device to the relay be any different than the
size from the relay to the battery?

Do the ground wires need to be the same sizes?

Where does one get the kind of female spade connectors with the little tang
on the side that keeps them in the plastic relay mounts that VW uses?

Thanks,

Jim