Wheel question

[kwin]

I have the opportunity to buy a used set of boss wheels, I don't know a lot about wheel sizing, but the deal seems to good to walk away from.
They are boss 304 wheels in Black Chrome, they have a few scuffs but are not in terrible shape.
The guy wants 300.00 for the wheels. Including two good tires that I would have to resell.
They aren't exactly what I want but for the price...
here are the specs
20 x 8.5
5 on 5
+14mm offset

I know the bolt pattern is correct, otherwise will they fit my 1991 suburban.
Any limitations? will they

Thanks for taking the time to help me out.