I just recentered my Hummer wheels with 3/8 centers. I cut my own centers and re-enforcement outer rings but there are several other to choose from. I am going to just post the sequence of pics but if there are any questions feel free to ask.
1. Cut out factory center. I used the outer ring edge as a guide and cut it with a plasma cutter. I suppose a torch could be used too but I would think a cut off wheel would bring the suck. They are already sandblasted.
I then designed and cut out my outer re-enforcement rings out of 1/4 and the centers out of 3/8.
I then welded the outer rings on the outer portion of the wheel. Only one wheel was out of whack but not too bad.
Gratuitous close up.
Then I made up a "jig" of sorts by using my factory hub with disc and a spare 3/8 center as a spacer. I placed this jig on a piece of 3/8 plate for as flat a surface as possible. I checked each one and all were very, very close in trueness. This setup gave me a 4.25 backspacing. Which is about as much as possible and still be able to weld the outer side of the center easily.
After tacking them in 10 spots (both ends of the spokes) I removed them from the jig and welded the backsides of the centers being mindfull of the heat and welding every other spoke till done.
Another close up of these welds.
Then after a long cooling period I welded the outer side of the center the same way. It is quite tight in there but not too bad.
Here they are together.
And here is one of the outers sitting in a tire.
I need to cut down my runflats yet but will get those done soon. I also bought new o-rings from Graingers and will paint them after it warms up a bit more. Hope this helps someone who is thinking of doing a set. Its pretty easy to do it just takes a lot of welding. Tab