Ilfochrome-A filters with Ilford Multigrade paper?

Hi All,

I have been using Ilford Multigrade Warmtone for some time now.
Since it will be a few months before I can find someone to carry (from
the US) the designated Ilford filters for contrast control, I am forced
to use Ilfochrome-A filters for adjusting the contrast.

However, I don't think they are working satisfactorily for me. I am
still figuring out the contrast I can get with the various Yellow and
Magenta filters from the Ilfochrome set.

Has anyine tried using these filters for Multigrade paper?

Specifically, what would the M50 filter of ilfochrome-A correspond to
in terms of Multigrade contrast? What could be the mapping?

I use a tungsten lamp in Vivitar enlarger.
thanks for any tips,
Sreenath