after more research, I now answer my own question (did all carbs have spark control valve when used with Load-o-matic distributor). And the answer is NO.
'55 and '56 Ford car shop manuals show the Holley 1904 1bbl carb for the 223 engine WITHOUT spark control valve. This carb did use a combination of ported and venturi vacuum via tubing from the upper main body throat of the carb routed to the distributor vacuum advance and a ball-check valve located in a vacuum passage between the main body and valve body.
The 1bbl carbs that did include the spark control valve did not appear until many years later.
Since this system as it was originally designed did not have the SCV, I am tempted to switch my valve body back to the one that does not have the SCV.
Still have not started this thing up yet, although I do have fuel bypass between fuel pump and gas tank completed and installed a smaller piece of tubing inside the fuel supply line to the carb downstream of the bypass line as an orifice to purposely create backpressure in the line (which should help to cause filling of the bypass line). It is hopeful that this installation might alleviate carb flooding. In conjunction with this, I also installed a 1/4" spacer between the fuel pump and the engine block which I hope will reduce the fuel pressure coming out of the fuel pump.
Some time this year, I will start this thing up and report my results.