whats up with Centerline and Backspacing?

[wildcat4]

I want to order new back tires for my 70 GS.
I currently have Weld wheels 8.5" with 4 5/8" backspacing.
But I found out one rim is bent a bit.
It appears as though Weld no longer carries my style (Zero Drag Style)
so the next closest thing is Centerline Auto Drags
however there backspacing in that rim is either 3 1/4 or 4 7/8.

I already have to put a wheel spacer to keep the tire from rubbing the inner fender well, and can't imagine going with MORE backspacing.
But 3 1/4 backspacing sounds like it will hit the outer wheel well.

What do I do?? :Do No:

[chris lee]

i'am trying to sell these
used centerlines auto drags..i had them polished.
3-1/4 back space or rears
fronts 15x4's
brand new yokahama's front and rear
rears 255/60/15 (fit good but can't go any bigger..275's rub on fender
front's are skinny's
$750.00 plus shipping
might have 200 miles on them..can e-mail more pict's
chris.

[wildcat4]

thanks for the offer Chris, but it sounds like the 3 1/4 backspacing won't work for me. I currently am running BFG Drag radial 325/50-15s which I love and don't want to go with a smaller tire.

Why would centerline not offer any 4 1/2 backspacing anymore?
Anybody else out there got any thoughts?