PLEASE HELP!!need to know if i need new rims installing 3" spindle lift soon!!!!
 

I have a 2004 ranger xl 2 wheel drive with front coil springs 3.0L.
I've ordered a fabtech 3" spindle suspension lift kit. After I ordered the kit the shop told me that I will not be able to use my factory rims when I add 31" tires.
I was also told that the new wheels I get need to have 3.75" backspacing or less.
I called around to a few other shops and got mixed answers some saying that they need to be 3.75" backspacing or less and others saying that it should be 3.75" or more backspacing.

I really need to find the correct answer as soon as possible. I can not afford to buy brand new rims and tires. I found a used like new set of crager soft 8 wheels and tires on craigslist for a good price. On the crager website it says that the backspacing on their 15x8 soft 8 rims is either 4" or 4.75".
WILL THESE CRAGER SOFT 8 RIMS WORK??????????
I would really like to know the answer before the lift is installed .
Any info would help thanks