As my signature indicated, I have the gauges and clutch covered.
As Robin said, I wouldn't do anything without installing gauges as step 1, which is what I did. HO's are noted for running high EGTs (I know, your truck is an ETC, not an HO), and I could hit 1300 degF pre-turbo when towing when the truck was stock!
When towing with the BHAF, Jardine 4" exhaust and Edge EZ, the stock clutch held fine, and max EGTs dropped to 1100 degF using the Edge-supplied boost elbow. The DD2 injectors pushed it over the line, though, and that's when the South Bend Con OFE went in.
Since you tow a 5ver that weighs 11,000 lbs and have a 5-speed transmission, I'd highly recommend an exhaust brake. It doesn't make it go faster, but sometimes we have to stop or go down a long, steep grade, and it's worth its weight in gold for that!
Rusty