Sam was running 37's at the end. I think he had RUF and some tacoma rears.
And FWIW here is my $0.02... wanting to run 38's is where you want to get to, but as someone else asked, what is the end rig going to see. Your sig doesn't tell your location so I can't assume wheeling style.
East coast is very different then west coast. Traction is everywhere in Moab, but can be hard to come by in the south.
I would just worry about it getting running and driving well before you throw a set of 38's at it. A stock rig with decent tires will get you a long way in one of those trucks. Steering, gearing, engine, etc are all gonna be affected by those big heavy tires and if any one isn't up to it you will spend alot more time wrenching then if you learn the truck first. You may have a couple builds under your belt but I am just speculating. The factory axles can handle 38's with some upgrades, but 38's and big power you will have to be a little easier with the skinny pedal.
As far as your actual question, I'd probably look into a spring hanger kit, everybody makes one so just pick you flavor, RUF, plan on some new rears, either chevy's or tacoma springs would be cheap, aside from that pretty much everybody will sell you some lift springs. Flex will either be creative or expensive, your choice. Shocks and plan on high-steer. Keep it as low as possible if you want it to crawl, if it will be a middle the sky it to help keep your feet dey.