Hey Steve,
I remember seeing something about that myself. Never have tried that technique, but thought I'd shot you this link. I'm doing a captured T34 and needed a German recognition flag for the hatch. Had a couple of people mention this place. I bought the flags that are on the link I gave here and I am very impressed. The customer service (well the whole process of buying...didn't need customer service per say), was great! Fast shipping. Great packing! Lots of info to help with the process of making the flag, and tons of selections!
Just thought I'd throw this out in case it might be of interest to you. If you want any more details, feel free to PM me.
Hope this helps.
Eagle90