Hi Phil
One practical way to solve your problem is to send a negative to a friend ,and have the negative printed to match in all five grades using the 0-5 filters.
You then on your enlarger match the prints and record the magenta or yellow settings you used to match the prints. This will give you starting points for filtration.
If you don't have anyone locally able to do this , you can send me the negative and I will make 5 prints for you.
As stated above this is a very basic method , but a way to get you in the ballpark for filtration starting points.
Bob Carnie