Getting the Caprice ready for summer towing

I have decided to use my 1994 Caprice wagon to tow a 4,200 pound travel trailer to several state parks this summer. The car only has 97,000 miles on it but is 12 years old. I am looking for advice as to what sort of preventative maintenance I should have done prior to the trip to avoid any possible breakdowns. The car has the 5.7 LT1 with the factory installed towing package.

Flush and replace the tranny fluid, add a trans cooler and a set of AirLift bags.