primary rod size by part number

[unruhjonny]

I just came across an unusual primary metering rod/needle part number;
#7047907
the number is from a 1973 Rochester book, and I have noticed it for a carb I have (#7043251);
Can someone please tell me which rod this number is?
I have come to understand that the rod size is generally the last two numbers in the part number, and this is the first instance I've come actoss which doesn't seem to work this way.

Thanks in advance for ypur help!!

[carmantx]

I believe those are 53c primary rods.

[unruhjonny]

/\ thanks!!

(if anyone can confirm this, I'd appreciate it!!)