For these situations i made my multilingual motorhome tirepressure calculator, in wich I take a reserve to the given load or different when only GAWR's given .
Also I use a saver formula then the american tire makers use to make those pressure loadcapacity lists , and even a bit saver then the European lists.
It takes care that the deflection of the tire stays the same as when maximum load and AT-pressure on tire, wich is the goal of all calculations.
so if you weighed give the seperate wheel(pair) weights and I will calculate and give a picture of my filled in spreadsheet.
will make one in next post for your GAWR's, but first have to google your tires for the maximum load and AT-pressure.
If you want to play with the spreadsheet yourselfes,here the link to the map.
First download it to your computer by rightclicking and choosing Download .
After download and eventual virus check , open in Excel programme on your computer, but Open office Calc can handle it too.