I'd really like to know too!
Best guess for middle of receiver is between 21.5 and 22" off the deck. That was based on a picture from somebody's I5-30FW. I'm new to the forum, we'll see if I've successfully attached that picture?
You are well ahead of me. I've have a 28SS-X on order and a JLUR already designated for Toad duty. At this point, the Rock Hard 4x4 front bumper appears to be closest to a match that is within the 3" margin of keeping a Blue Ox Tow bar horizontal.