Lift & Tire Help/Opinions

OK just starting the my cheap lift on the Comanche Devil. Put in the T-Bird springs upfront. Netted 4" lift, today I made sway bar disco's from 2000 Grand links , this weekend I will be lifting the rear, so here is the Question. Do I re-arch the spring pack to achieve the 4" needed or make up longer shackles, or do the both? And about how much arch to net 4"? I know for a 3" lift the springs need a 5" arcs for a 4" would you go 7" or 8"arc? Don't want to do a soa because i will get 4.5-5" and thats too much. Now for tires do I go with 31" or 32"? I want some opinion I know there are only a 1" but what is the pros/cons. Need some experience opinions.

For the tire selection, every person on here will likely give you a different answer. I personally went from 31x10.5x15 to a 235/85/16 and I am quite pleased. I went from a mud tire to an all terrain also. The new tire ends up being 31.7 tall and 9.5 wide...almost exactly what I wanted. I spend a lot of time on the highway so I knew 32x11.5x15's were out of the question- I don't need or want a wide tire. I also didn't want a 33x9.5x15 or 33x10.5x15 because I didn't want to go another inch in diameter. I am running 3.55 gears- but being that I drive highway and it's 98% free flowing I can afford to be under geared. Driving 70-75MPH puts my RPM's back in the peak efficiency range of about 2100 RPM's. I would not do it for a lot of stop and go or very hilly terrain, I would have kept 31's were that the case. I could go on but I'll stop now.
BTW, I run 4.5" lift

I know you don't want to, but doing a SOA isn't that much harder than unbolting your springs, having them re- arched, bolting them back on and changing the shackle.
Get the gain in lift, then go back to the front and level it off.