Help with what size rim to go with on rear of my 70 swb

[Chris04]

Hey guys I'm super new to these trucks and was wondering if I could get some help? I got a 70 swb fleet side I currently have it lowered 4.5/5" in rear. My next goal is a set of wheels and I want to go wide as possible on the rear wheel basically I want the biggest lip I can get without having to cut any on my wheel walls or bed. I'm going to do the 5 lug disc break conversion all the way around then purchase my wheels. Problem I'm facing is I read somewhere about you could have your rear end shortened to 60" and run a pretty decent wide wheel on back. I'm pretty sure I have the longer 63 1/2 rear end I'm not 100% sure tho and guess it don't matter if I'm going to have it shortened anyway, so if I go ahead and get my 5 lug axles in and have the rear end shortened to 60" how do I know what back spacing to go with? Have any of you done this? Hope I
Explained it we'll enough! I just don't know what's the widest wheel I can go with on a 60" rear end. Any help appreciated guys


I'm looking for a wide wheel like this

http://i173.photobucket.com/albums/w54/skaylad/Mobile%20Uploads/image_zps83b597ce.jpg[/IMG]
I know you guys like pics so here is mine working on it slowly