Welcome!

If you haven't seen it in the FAQ already: Unless you've already got your tags in perfect order - start working on them...

Quote:
remote start an aftermarket head in 'aux' from the Empeg?

Not as such (IIRC), no project to control a HU and flip it to AUX... but if the HU stays with last selected source between power down/up it should stay in AUX In mode (or radio if you chose that last before shutdown...) it should pretty much do what you're thinking of if it also is wired and set to automatically come on, right? If it draws the actual power from the constant +12V wire you could probably just wire the ignition lead to the empegs remote turn on lead so it turns off along with the empeg. (and if the current draw is too large you could put a relay inbetween I guess...) IIRC, some HUs might be able to switch to AUX in upon activating the "phone" lead (normally to be wired to a handsfree kit)...
Just some ideas...

Quote:
Oh, yeah, sorry, I won't be able to make it to any Euro-meets, I'm in California! lol

That's not a valid/sufficient excuse! At least apparently to some nutcases...