I won't spend too much bandwidth on this since you've thought it all out and made your mind up already, but the bulk of your logic of why this is a good idea is not technically sound.
I'll expound on it if you want. You would be far better served putting that $8k towards the upcharge for a diesel.
Sadly it's already too late. I bought the gasser. I haven't made up my mind on the procharger yet - especially after someone suggested Whipple.
I won't be running off to install a charger right away. It's only a consideration if I have issues hauling.
Right now I don't think I will as I'm looking at only doing 11,000 traditional.
Regardless I'd want to break in the new engine etc first. If I decide I want a charger it might go in at 30k miles when I'm sure I won't need any warranty claims on the engine.
I also thought it was really worth mentioning in this thread for others who might be stuck in my decision.
460 torque gas vs 975 diesel was a hard decision.
700 @ +6psi super safe conservative supercharged while having ALL benefits of gas vs diesel? Plus getting MORE hp? In my mind that was a freaking no brainer choice.
Look - I've used to track motorcycles when I was young and dumb. I'm pretty skilled at operating gas engines in their preferred rpm.
At this time I don't know how the truck likes to drive empty vs under load. I did watch one YouTube hauling 14k lbs 5th wheel driving both gas and diesel. I noticed he didn't know how to drive gas correctly. He was having issues at 12k altitude in 7.5% grade going uphill and maintaining 60 mph.
I noticed he kept it at 3k rpm and that he was flooring it on the peddle. He never gave the transmission a chance to downshift and get it back to 5-6k rpm which is the sweet spot based on research and the procharger/Whipple tuning curves I've been looking at for the truck.
He was also not using his paddle shifters.
I do say gas takes more skill to drive it optimally than diesel going uphill...
Which brought me to a hilarious point on the YouTube. The poor guy was looking all over for the exhaust brake on the gasser



The gasser doesn't need an exhaust brake. It's clear he doesn't really know how to operate it and so on.
Then my partner has never towed before. That's a huge consideration for me to go with gas vs diesel too. I feel safer if he learns how to tow in a gasser personally. Like imagine if he forgets to turn on the exhaust brake or forgets to take it off etc.
Then finally - we're not towing every single day. It's only towing 5-6 times a year. If it was towing every day then yeah I'll prefer diesel. I really don't know if I'd want to hear 5k rpm whine all the time in that situation.