I was planning to purchase a set of Centerline Grizzly's in 20X8.5 and a set of Toyo Open Country AT's in size 305/50/20. They will go on my 2005 HD and the only mods I was planning to do were shocks and a leveling kit. My question is whether I should go with the +6 w/ a 5.0 backspacing or +32 offset w/ a 6.0 backspacing. Thanks in advance.:)

I went with -1 offset with 4.65" backspacing on a 305/55/ 20 and everything worked great with a little minor trimming.

Thanks Shadowrlc. Any others.

I would go with the +32 offset. I run H2s which I believe are a 17X8.5 with a 5.75" backspacing. I think running too much offset is really hard on all the front end components on these trucks, especially with front axle weights over 4k lbs.