[BIGglaSS]

You work fast! I'm glad you're happy!

1. The x-over settings should be fine the way they are. Let me double check the manual, but as I recall, the jumper settings will raise or lower the volume of the tweeter +/- 3 db. If the tweet is too bright/harsh, then you can experiment. Otherwise, leave it alone.

2. I think the retro HU sub output is mono, so this doesn't matter. The Amp input has L -R. Usually only one input is needed, so I would say that it will work just fine with only L input. If the RCA cable from HU to amp is only a single, don't worry about it. However, it wouldn't hurt anything to also use the R input if you are using a paired RCA cable.

3. This is a simple 3 band EQ. It adjusts the tonal output of the receiver, or pick a pre-set tune, Classic/Pop/Rock