I think you do not have the OEM puck system, since you are asking about installation? If you want a rail hitch, the B&W Patriot is one of the best, for the dollars spent.
It is not hard to install the rail system. In most cases, you can buy the underbed frame mounting brackets, designed to fit your truck, without drilling. You just need to drill bed holes to attach rails to brackets.
While a 7-pin in bed plug may be handy, it is not needed.
Just stay away from the less expensive entry level hitches. I know you already know this, having owned a Hensley.
Jerry