Yea don't look at the axle ratings at all...that's where math gets really fuzzy with trucks.
Your gross axle weight ratings added together are likely about 500-1000 lbs more than your GVWR. This means you can technically be under your axle ratings and still be above GVWR...
This is why a lot of people disregard the payload sticker and go with axle ratings and try to stay under that. It's not just half ton tow'ers who do that. Lots of 3/4 ton and 1 ton tow'ers do the same thing.
I can't with my minivan. My axle ratings added together equal the GVWR.
Good luck no matter what you decide to do.
Thanks,
Jeremiah