The 1937 season was a time of transition for Philco. They phased out the 1932-36 decals (Radio Daze DCL-PH8 ) and phased in a new, slightly different font (DCL-PH1 and some others).
I don't have a 37-620B, but I do have an AC/DC 37-641B. I just went to the basement and took a good look at it. It uses the 1932-36 DCL-PH8 decal.
I would normally say to use DCL-PH1. This has four sizes on it; you would want to use the 9/32" x 1 9/16" size.
But since many early production 1937 models used the DCL-PH8 decal, and since I know you had to buy some recently for Mike's 66S...my advice is to use another of your DCL-PH8 decals on your 37-620B. It is also correct for this set. (And saves you from having to buy another sheet of decals.)
Raise it up so that it is centered completely within the upper border and above the black horizontal line where you currently have it placed. You have it placed too low right now.
(I hope you can do this without ruining your new faux finish.)
It appears to be a bit off center (just a bit too far to the right) in the photo.
However, the PHILCO decals were not always 100% centered from the factory. When these things were being built, the decals were applied by humans who made errors. If the error was minor, the cabinet went out the door anyway. Thus my comment, "that will work."
Well. I think only one of us would notice such a small thing. But I did paste-ups and ads a long time ago, and saw it immediately. The font appears to be equal length for all letters so PHI-Center line -LCO would be most corrrect.