Pete,
I have a Reese 14k/1400 tongue hitch # 63970.
I pulled my 24' Haulmark (10k gvw) with a golf cart in the front and my 68 Camaro using a 2001 Z71 with a 5.3 and 3.73s for 2 years before getting a 2500 Dodge 5.9. You should have the biggest trans cooler on the truck as possible.
I used the equalizer bars with no sway control. I had no other spring helpers. The equalizer hitch with the 1200 lb bars worked great. I only had issues with a head wind. Otherwise, put it in tow-haul and let er rip.
I got about 8.5 mpg.
Clark Doukas