Here are some approximations. I did these when I was looking at replacing the 1Meg Reverse Taper Bass Pot.
Bass Pot and Tone Pot SweepsI do not know the inductance of the MFD pups (I guessed 1H). If my guess is wrong, and it probably is, the curves will shift. But the relative change with pot position should be similar. Also, the tone and bass controls interact with the entire pickup circuit. As you go from a soloed series pup to a pair of parallel pups, the source impedance varies by a factor of 8. This means the passive bass and tone cut curves will shift by quite a bit. Assuming the dominant factor is the square root of LC, we would expect to see the curves shift by a factor of 2.8 across the range of soloed series to a pair of parallel pups.
Series pup soloed => 2R + 2L source impedance
Series pups x 2 => R + L source impedance (same as SC solo)
Parallel pup soloed => R/2 + L/2 source impedance (same as SC pair)
Parallel pups x 2 => R/4 + L/4 source impedance