Yep 98G, that is what I was thinking. The 395s being in better shape, for the most part, and more easily available. Both tires can be found brand new but older production tires, even new, won't stand up as long to equal amounts of use/abuse.
Right now the truck goes 50-55mph without much effort. It is happy between those two speeds. Anything above 55 is a straining point unless it is downhill. The only reason I may/might do the tweeks is if the truck with the 395s still has a hard time rolling along at 60mph. The other issue is pulling my off-road truck behind it (trailered) uphill. It doesn't take much of an incline to slow the beast down to 45mph. If I am towing something I imagine that if my truck even thinks there is an incline coming, it will start slowing down. It isn't a compete dog uphill but it does take its merry little time on every hill it sees. Which I knew would be the case when I bought it. However, if I can get a bit more pep out of it at no expense to engine life then why not?
I am going to get the RoboTool for the tires/maint on the truck. If I find I need something bigger then I will order at a later date. I know the torque on the Robo is lower than a 1" but this truck isn't a M1 or Bradley either.