So, what we have here is 292, HEI ignition, hydraulic cam and lifters, .035" gap plugs, 500 or so idle rpm, and has been setting for 5 + years on stand after a rebuild.

Is that about right?

Carburetor meter should not effect idle, float level will. My concern was about the size of the carb. 250's use a smaller bore and rebuilders tend to swap parts not caring if its right or not.