I think your paint / por quantities are higher than they need to be. I did long fleetside and used 1/2 gallon of house paint. It went on light after por.
Por - i dont recall specifically but i dont think it took over 1 gallon. I applied multiple coats of both, but dont recall how many coats. That was 12 yrs ago and it is a strong finish. Gets hot in the sun, but that is the only negative.
I calculated 2 gallons of each, expecting to have some leftover. I broke down the process into minutes for each bolt for removal and it was around 5+ hours. 18 hours for sanding, sealing, painting, 2.57 hours for the 7 steps. 3 to 6 hours for installation. 27-30 hours Total. Breaking it all down that's what I got. So basically a weekend project after the boards are prepped and ready. Everyone was busy, so I decided to tackle it, and knowing the condition of the truck, I think the estimated time is right. Shocking, but after breaking it down, it is what it is.