How Do I ID The Printer Of 23c USA Presort Stamp

Just going through some of my stamps and came across the 23c USA presort issue. If one does not have the PNC is there a good way to tell who the printer was. I know I have some that are a lighter color but pretty up in the air as what is what between 2606, 2607, and 2608.

The key answer is at the bottom of the stamps in the word "First-Class" and "23":

#2606 = "First-Class" at 9.5mm long and "23" at 6.0mm long;
#2607 = "First-Class" at 9.0mm long and "23" at 6.5mm long;
#2608 = "First-Class" at 8.5mm long and "23" at 6.5mm long.

As suggested above, there is a clear visual difference between the numerals in #2606 and #2607 (with the numerals on #2606 being much more compressed).

Also, the #2608 is much more purple in color than the others, which are primarily blue in color.

I think I have some examples I can post. Stand by.

Edit: Here are the examples:



In answer to your initial question:

#2606 = Printed by American Banknote Company;
#2607 = Printed by Bureau of Engraving and Printing; and
#2608 = Printed by Stamp Venturers.

Thanks WT1,

After your descriptions it made the ID process a snap.