here is a good rpm calculator, maybe an idea to check it out. if you know the trans you have you can figure out the final drive ratio and the ratios between gears. plug in a few specs and the calculator will finish the last one for you.
http://www.advanced-ev.com/Calculators/TireSize/
here is a tire size comparison calculator that allows you to compare a few tire sizes. it also has tabs for a few other things like finding tire sizes for different wheel sizes but with the same overall height, etc scroll down for those things.
https://tiresize.com/comparison/
gearstar site has the gear ratios for the 700r4 here
https://gearstar.com/overview-700r4-...hicle%20speeds.
2.73 seems like a highway gear more suited for a 3 speed trans. it's your truck so you build it like you want, just info for you. you can always swap the axle ratio later if it turns out that you don't like it