Going through the process of installing a FireHawkII hitch by Putnam on our Silverado Crew Cab Classic. Will do that Tuesday 6 Mar.
After that is installed, will back the truck up to the 5er to see if we need to modify the trailer part of the connection.
With luck, will not have to modify the 5er. If we do have to modify the 5er, there are pictures on this site where it was done before and I will show you how to access it.
Will keep you posted on how things go.
Do a search on this site for Firehawk II 5th hitch
and you will see some modifications and hitches.