I use an Aristo VCL 4500 which allows me to dial in a contrast from green to blue/violet as you mention. It also has other settings that can turn off the green or blue or have blue max. It has a separate switch for normal or split printing. If this is the type of light except for the size then: the on/off switch (not the main power switch) in the "on" position will give you blue max -- blue only at maximum brightness; blue/off -- blue only with adjustable brightness control; green/blue -- green and blue combined with blue intensity being fully adjustable (probably the setting you will most prefer); with that switch in the "off" position it will give you blue max. -- blue only at maximum brightness; blue/off -- off only; green/blue -- green only no blue.

The more blue the more contrast and the more green the less contrast. A setting of 2 would be a starting point. If more overall contrast is needed then increase toward 5 and conversely less contrast toward 0. You can expose different areas at different contrasts for example you could give an overall exposure at 2 but some part could be burned at 4 if that is your desire or you could go the opposite way or hold back and then expose at some other contrast. Try a test print at different contrast settings and you will see the effect.

I use Ilford MGF and it works fine. I hope this was of some help.