22" GM transport or 20" Detroit Steel for 89' Suburban

[jathur02]

I want to swap out the 20" Vision wheels I have on my Suburban now with 22" GM Transport wheels or have Detroit Steel make a set of 20" wheels with more rubber. I tried asking the original owner, but I haven't had much luck yet on what offset they are. Do you guys know what the pattern/offset usually is on a 1989 GMC Suburban? It's dropped 5" in the front and 6" in the back (air shocks in the rear), so I wanted to make sure I wasn't going to rub if I upgrade to a 22" wheel. I would also have to get adapters to make them work I believe, so I didn't want the 22's to stick out too much if I did have to use adapters. I searched everywhere and couldn't find an older square body Suburban with this type of wheel, I'd really like to see what my truck could look like with them on there. Any photoshoppers out there? ha..I included a couple of pictures.