Thanks guys this was the info I was looking for.
Brodie 55 and Rono if you two could take pictures of your linkage that would be great. I think the Edelbrocks make it pretty easy if set up is like the 245/270 HP GM's. I think I have my linkage figured out. The lead carb will will run from about 1/4 to 3/8 throttle on the front barrels of the rear carb before the second one (front) starts. The hole will be drilled in my linkage when I hold them both wide open. A Corvette type slider will do.
Brodie55 i would like to know which WCFBs you are using, I'm assuming they are small base. I'm planning on those also. Funny that you had trouble with the rear on idle after sustained cruising. I have had some problem with that using just a single one on my "A" manifold currently.
My E-257 manifold is ready along with the one carb I'm currently using. The second carb is due back from the restorer/rebuilder very soon. He has a long lead time and every carb is test run.
No Shortcuts: If you cannot fine a 245/270hp Corvette from 57 to 61 Look on ebay for their intake/carb set originals run big buck and closes about half but they do show the linkage and how the front carb is lower on the front carb arm to make them work correctly. Doning this on a Ford takes a little enginuity (like my spelling?) because the arms on a Ford linkage are shorter and don't pull straight back. Once again thanks.
PS: as a side note I discussed this with Ted and my first running of the engine will be with the rear carb only with a plate where front one goes to see how every thing operates.......