** Am having trouble getting a recently rebuilt 261 started. {First Start} - Valve lash set to specs - timing set to specs - all six spark plugs have good spark - known good carb installed but engine will not start. Not as much as a pop with above settings. If I retard the distributer {counter clockwise} as far as it will turn the engine acts like it wants to start but won't. Have checked and rechecked all settings but still no start. If anyone has any thoughts that might help all greatly appreciated. Thanks