You can try to use Ilford under the lens, glass (or into filter drawer, plastic), multigrade filters. Just use unfiltered light from enlarger head and use Ilfords filters. I have Opemus 5 and Magifax 4 with colour heads (Old Meochrome for Opemus and newer Meochrome 3 for Magnifax), but I will buy Ilford under the lens, glass filters. No more guessing "is grade 3 60M20Y or 65M15Y, or...?"
To say, as I have b/w heads too for both enlargers I am OK, I don't know how light from colour head (that is halogen, unfiltered) works with multigrade filters.
Ilford filters should work fine with ordinary b/w head, but if someone tried halogen light from colour head (unfiltered) to use with Ilford multigrade filters (especially glass under the lens type), I would be gratefull for informations how that combination works.