Hi Ryan
As Karl said, use the masking tape - you still can repair it and it will have a better look.
It's an easy fix, with a big result!
Another thing that you could try to do, even without an airbrush, it to give it a subtle black wash, so that the details are noticeable. After that, drybrushing the afected areas with a lighter shade of the base colour wil help give it a little volume. 
I don't want to be a pest or anything (trying to help) but you can see this Feature:
Typ VII-C or this Review:  
Typ XXIII Different methods, with good results (although Glenn's u-boat it's much better IMHO).
Don't give up on it - just take your time 
 
 
Skipper