[Alan Roehrich]

I'm not saying it will solve the problem if you leave off of a two step.

Here's what I'm looking at. The carburetor is a Q-Jet, correct? If so, then this applies. If you are at WOT on a two step, there will be no pump shot, and you will have very little vacuum, so if the carburetor still has a power piston, spring, and metering rods on the primary side, they should be all the way up, or nearly all the way up, so the power circuit is already working. Some cars even get the secondary air door open on the two step, some don't.

So, leaving on a two step may allow the carburetor to function in the simplest way possible. If it happens to help the situation, it gives you a few things to look at. The same applies if it makes the problem worse. And if it changes nothing, you may want to look elsewhere.