Yep it's a V35. I use graded paper and the MG head above actually has one of the two Dicro filters missing (I got it that way). So it is useless even for MG paper and I thought I'd mod it to hold a photo-paper-safe red filter.
I put a thermometer right where the light hits the Dicro head glass filter and it got to 200F. A Roscolux can get to 220F and that's cutting it close for comfort.
Seems the most safe route is the Edmund glass filter cut to size ($40ish) or buy a b/w only head ($100), like this Leitz part:
Or a under lens filter, which I have but just don't really like the ergonomics:
Really not too much of a bother just want to put that broken part to work...