this is a MK1 so the pin out is correct I guess they added some wires to the MK2

I bought this used so no manual the one on the empeg site is for the MK2

you are correct the plus only goes in one way I didn't even try to put it in (paranoia is bad) it looks like it would go in either way

now if someone know if the 12v goes to ignition or constant I will be ready to put it in
I am guessing ignition otherwise it would never shut off but then when the car gets shut off the power just gets cutoff that sounds bad also

thanks