I see the current rating is 1.5Amp. That would be enough to energize relays. The fuel and EFI relays would be fine with that, but I would prefer at least a 5Amp switch. Need a caouple momentary on switches for the wipers and starter also. The starter should have a relay. The wipers are going to have 2 switches in parallel, 1 momentary for light rain or mist and 1 to turn the system on. Probably wire the wipers for the medium speed. Could use a relay here also, but if we go just switch, 15Amp rating would be a minimum. Isolated circuits are planned to be fuel, EFI, starter, ignition, Fan(heating or cooling the cockpit[yeah, I wrote cockpit]). Might consider a sprayer to wet the radiator in case of overheating.