ABS milling goo

I am looking for the optimum settings and bit combinations for carving engravings into 1/16" thick ABS. There is a very thin color later on top of a white sub layer. I am going in very shallow to just remove the color on top.

I set up a two stage carve using a 1/8" spiral upcut bit for the roughing and a 30 degree V bit for the detail passes. I have my 611 router speed knob all the way down to #1.
Using the recommended Easel settings (40 in/min roughing 24 in/min detail) produces a buildup of melted plastic on the bit that leaves color smeared in the carved area as well as around the uncut area.

I went in and custom set my feed speed to 25 in/min and my detail cuts to 15 in/min, but if anything, the melted abs goo is even worse.

I am looking at switching out to a two flute straight 1/8" bit for the roughing cut.
Any other suggestions?

Thanks,
Jeff