You may have a fuel injector leaking out into a cylinder once the truck is turned off. If you put your foot to the floor while cranking it, does it start in a faster amount of time than if you were to have your foot off the pedal trying to start it?

Borrow a fuel pressure tester and hook it up (super easy). Monitor the guage as you have a friend turn the key to the on position, if your pump is working properly the guage will jump up to 40ish psi instantly. If you let it sit 20 minutes or so and pressure is leaking off this points to a fuel injector. (I am assuming your pump is good because it's new) If the pump were bad pressure would build to 40psi slowly and leak pressure of fairly quick (10 minutes or so your down to 15-20ish maybe less). By cycling the key a few times as 'Hey You" suggested you are allowing the pump to run a few times and pump up pressure in the line. When everything is running properly the fuel lines should always hold some pressure

If it helps to put your foot to the floor when starting this is because there is to much fuel in the cylinder, by flooring it you are letting in more air to ingnite that fuel, thus you get that flooded smell when it starts.

thats my guess

 

+1 on the injector issue, was going to post that info after finding out the results of a pressure test(need pressure tester). On the other hand, if it does start right away when pedal is to floor, might just be an IAC problem.

 

^ yea could be a cheaper rout to check out before paying $50 per injector if flooring it helps to start