 Re: Under base an outer glow?
I wouldn't make the under base the exact same, you're most likely going to encounter white peeking out even if registration is dead on (this is usally do to bleeding or that the underbase is on a looser mesh).
You have 2 main options, either reduce the under base fade by about 40-60% this allows for any screen shifting on the press. The lime green ink will blend into the fabric when it's off base, this gives a nice effect in my opinion.
If the glow isn't very big (wide enough) to actually do a reduced under base fade another thing i've done is produce the glow as a halftone bitmap in photoshop. create the choked under base in photoshop also by chocking the bitmaped halftone you create. If you want to do it this way, just ask and ill explain further, it's a bit more work with a few steps but it works really well. | 
