This article is from the Darkroom
Work FAQ, by Cees de Groot
Yes, but there might be small differences in the grades you get. However, a #2 filter will always give a softer result as a #3 filter, no matter on which paper you use it.
My humble opinion: the subtle differences of mixing up filters and papers are probably smaller than the differences introduced by the fact that you probably use another developer, enlarger and darkroom than the factory test facility. So you need to test anyway (I test by contact printing a step tablet).
 
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