Did you ever get this going? I would probably start out with ModerDave's suggestion, but I'd also try it in a number of other ways. One other way might be to go SF-2>F-1X>MPX in the effects loop. I'm using an F2B in front of an MPX and then to a power amp, and that works pretty well, except that running the outputs of the MPX to both the amp and the PA can cause noise, so if you have it in the FX loop you can make use of the F-1X DI, which is an excellent DI. I end up using a cheaper Radial, but it's another thing to carry around and doesn't sound as good as the Alembic DI.
It all depends on the sounds you want to go for and what bass you are using. If I added the SF-2 to my rig, I'd probably do it before the F2B and have it all in stereo, using the F2B to mix it to mono for the MPX. On the other hand, if I continued the stereo path into the MPX, I could then set up each pickup with its own effects chain (the MPX is nice like that) and do what Chalie did all in one box. Just keep track of the gain structure so that each part of the chain doesn't overload (or under load) the next.
Have fun!