Thanks again! Now I just need to figure out what size the nut is on the cable. I don't have a short box end to get in there and I just can't seem to get anything to fit.
Just wanted to report back to close this case...the tightening of the throttle cable did the trick. It's idling now at around 1,550 in the water now which is so MUCH better. Thanks to all for the help - mikidymac!