Superliner end dump

How’s it going fellow drivers, I just received my build sheets for my
1990 Mack Superliner 713
E7 400
13sp road ranger

Wanting to haul end dump this year
Can anyone help me understand the build sheet? Seems to say 12k fronts 19s outback for a total of 50k. Does that mean I can only haul 50k? Seems light to me here in Indiana a tractor/24’ trailer can scale out at 73230.

 

That’s what I thought at first but my mind seems to overthink everything lol

 

I know I have to look at the bridge law to see how much I can carry legally. I just wanted to make sure the truck could handle that weight