Bike Forums - Schwinn Ace? Anyone Familiar?

Hello, I recently came across an old springer-forked bike in the neighborhood that a neighbor was throwing away. I grabbed it and it now resides in my garage. The springer fork is what first drew my attention. I do not have an extensive knowledge in vintage bikes, but almost everyone is familiar with those old forks.
It turns out the bike was not a schwinn but it has the headtube badge that states "Arnold Schwinn" and "Ace" in large letters in addition to some fancy airplane-like drawing. I wasn't aware that Schwinn made bikes for other companies, but it does make sense since they were one of the biggest producers out there back then.
Some checking on ebay has piqued my interest in the bike even more. Although it is quite rusty in some places, at least some parts from it are commanding some pretty impressive prices, including the aforementioned "Ace" badge.
At any rate, I stumbled upon your very informative website, and I got to the date code part, looked up my number to no avail. I was wondering if anyone could be of any assistance.
The date code stamped under the bottom bracket is as follows: D03690.
I beleive t to be a pre-war bike, but could you provide verification of it's date of manufacture? It's a ladie's 26" Ace model.
Any help you can provide would be greatly appreciated. Keep up the great website!
Thanks in advance, Gino