Bummer of an update. Tried 'em both, when I ran the first one (active with gain recovery stage) off of the same battery as the overdrive I added it to the volume dropped by half. Not good.
As for the passive one mounted on the pot, I can't seem to get it to fit right in the already cramped RACO electric box I'm using. So I got some questions:
1:Anyone know of any other decent tonestacks?
2:Anyone have schematics/layouts for said tonestacks? Active passive, whatever.
3: Does an active tonestack need its own battery? I don't think so, but there was a huge volume drop when I added it on to the existing battery.

No shouldnt need an extra batt to run a single transistor. Ive added the BMP style to many pedals never had a huge drop in volume with it. Its usually added right before the volume pot not right before the output jack. There is a tonestac calculator free on the net that will allow you to adjust the caps and resistors. Getting the right caps can make a big difference. Wrong value caps can send to much signal to ground. If you add a switch to the ground for the tone controls you can bypass it to see the difference.
Right before the volume pot, how do you mean? I ran the output of my pedal through it on its way to the jack.
The wire going from the output cap to the volume pot. It usually goes between the cap and the volume pot. Have a look at the original big muff to get an idea.