@79th Pa, thanks for the feedback, much appreciated!
@45div, yeah I spray primed them in black with a rattle can, and then did a Zenithal dry brush. I'm currently using Citadel Contrasts over it.
It's working pretty well, but the finsish is a bit rougher than I anticipated. I think for the rest of my Waterloo sprues I'm going to use an airbrush instead, and do a pass of gray followed by a pass of white. Will be much smoother. The manual dry brushing creates kind of a gritty look that I think would bother some modelers. In this scale however, the final result is still prettey decent when they are all ranked up together.
One of the reasons I went the rattle can route is that I didn't feel like setting up my airbrush so I just decided to experiment.
For all my Epic Scale Civil War, those were all spray primed in solid white with a rattle can and then I used Citadel Contrasts over that. Solid white primer is great to use under the Contrast paints.
I'm using a similar technique to a fellow on Youtube who runs a channel called "Miniature Realms." He's got a great channel and has all kinds of useful tutorials for painting Epic Scale.
Here's a link to his video where he paints some Waterloo British:
youtu.be/Phudv0_HCZ8