HELP!!!! How will overstay affect my spousal visa app??

[NYUSUK]

I've begun filling out the e-fastrack application for my settlement visa, but I've noticed that it's slightly different (i.e. more detailed) than the paper/PDF version, and it doesn't seem to give a space for "Additional Information," so I don't know where on the form to explain my situation.

My husband and I have been a legitimate married couple for almost a year, but I do have something in my past that makes me nervous...

In 2003, my husband (then fiance) and I decided to apply for a fiance visa for him to come live in the US and marry me. I went to the UK in summer 2003, then went home for a few weeks, then went back in September 2003 to help him with the visa application. Well, as some of you may know, the US visa process is much more convoluted than the UK process, and it ended up taking about 10 months before he got his visa. I stayed with him in the UK throughout that time to help him and to be with him. Obviously, I overstayed, although I wasn't aware at the time that I was doing anything wrong.

On the e-fastrack VAF2 application, it asks whether I've visited the UK before, and THEN (this is the difference from the paper app), a text box pops up asking for the dates and duration of my visits.

Obviously, I can't lie (even though I know they most likely have no record of when I left the country), but will this talk to up my chances of getting a visa? I didn't try to work while I overstayed, and all I want is to be with my husband!!! From what I understand, since we are legit, I should still get my visa, but how much longer will it take? We're applying online, then going in person to the consulate in NYC. Please advise!