Holley bowl trouble

Ok guys, scored a pair of Holley 600's (list 1850 model 4160) yesterday. Bolting them on a Weiand 2x4 intake for a 394 Olds. I can only get one carb bolted down as the rear bowl on the front carb hits the front bowl on the rear carb. I need a pair of bowls that are around 1/4 inch shorter front to back. I remember reading somewhere a long time ago that there were some available. Any thoughts?????

 

Pretty sure somebody (Offy?) made 1/2" thick cast aluminum offset spacers for that purpose. Looked like an adapter but shifted the carbs slightly front and aft.

 

Here's some http://www.hothemiheads.com/intake_manifolds/carb_adapter_offset.html

 

THANKS!!! Now does anybody have any spares???