OFFY DUAL 1BBL Intake question

I've only seen a couple of sizes that holley has(therer may be many more but I've only seen those 2 sizes for a long time. I think it's either 6-32 or 1/4- 32 sizes . Open it up and measure it. I've seen both sizes on summit racing. I'm doing the same conversion and just got the linkage to the carbs done. haven't got to the jetting yet,so I'm no help there. but I will be looking for jets to change mine out.

and if I can't find them I will have a gunsmith friend of mine solder and drill mine.