need 20/22's tire and size recommendations for lowered c10

[full foot notch]

so I've got a 72 long bed 2wd, and im wanting to install either 20s or 22s all around on the truck (no 20 in front and 22 in back combo). apparently its got a 3/5 static drop on it from the research I've done on here for spring heights and all. is a 90% black truck with satin hotrod black SEM paint so im going either all black wheels or black with chrome accent wheels to tie into the bumpers and door handles and some trim.

current wheels and tires are American racing Novas 17x8 on 255/50/r17 nitto 555 all the way around, the online specs say the BS for the rims is 4.5 inches. online tire calculators say the tire should be 27 inches tall but with tape measure at center of wheel its 26.5 inches tall, to the bottom of the fender lip in the front and rear is about 28.5 inches tall, and from what I can guestimate the safest height at x8 width would probably be 30 inches without scrubbing. at 30 inches its an inch or two up inside the fender well.

for wheel width for the 20s/22s I would probably want to go with an 8 or 9 width in front, and TBD a 8/9/or maybe 10 width in back for more traction since its got a built motor in it along with a swapped in built 700r4, but it seems with the current wheels in the rear I have about 2 more inches between inner tire bead and the wheel well before it would scrub in general and most likely any further lower.

in the rear it is factory drums but will be converting to impala ss disk rotors later this year. I don't know if that affects axle width/backspacing placement.

based upon given info what do you recommend for tire size and backspacing that would allow for ease of driving and turning. its going to be a cruiser with the occasional hot-rodding it. also keep in mind I would like to keep some rubber between the rim and the road as florida doesn't have the most perfect roads and railroad crossings, my thought was to go with a 40 series sidewall (stepping down from current 50 series sidewall) to use the plus sizing math while keeping overall diameter down, but would still allow for idiotproofing.