Express 3500 Cooling Improvement

[SixtyThreeL8]

I have a worn-out '05 3500 series Chevy Express and so I recently bought a replacement 2016 3500 series Chevy Express with a blown 6.0 LS engine. My son and I just installed a replacement 6.0 LS with 11K miles, but I am trying to make improvements to cooling. My experience with the 2005 Express pulling a camper tells me I will have cooling issues on my '16 Express pulling a 23' camper.  In cooler weather, my '05 ran fine while towing.  But in Summer months, with dual AC cranking going up inclines, I risk overheating.  The stock cross flow radiator has three rows (for tranny and oil?).  Should I just add electric fans and keep everything else stock?  Should I add separate tranny cooler (& oil cooler?) and get a custom radiator without those cores?  With all the Express vans out there pulling campers, I find it puzzling this "problem" doesn't have a pre-dined solution.  Another thought - does the Express 4500 (built into large RVs) use the same cooling setup I have in my Express 3500?  Any help would be appreciated.