There are several ground wires on the motor. When I swapped out my 22RTE to a 22RE, I found a ground on the drivers side, down by the alt. (IIRC it comes from alt. harness), one on the back of the head by the firewall, one that goes from the motor mount/block to the battery (battery cable), and then a small one from the battery cable/post to fender. So, kinda four but two is like one.
