Just a suggestion......check out the Holley/Weber carbs offered at a bargain price from Tom Langdon (Stovebolt Engineering Co.) Think you'll find that a pair of H/Webers are better suited to the 261 than the C/Webers.
I've used the H/W's and the C/W's on my truck engines and can verify that they are a terrific replacement for the leak-prone Rochester. In addition, both the H/W and C/W eliminate all the other negative issues of the worn-out Rochesters and will allow you to really enjoy your truck.
Dave
