Do you need servo assistance on a BEC? where would you connect the vacuum hose to if you were to fit a servo?

Not usually, no.
The car's so light it's not required.

Yup, no need at all on such a light car, all it will do is severely dull the braking feel.

Nope not required on 7's

Brakes ..............pah........for girls

Save weight and remove the middle pedal too

I'm using the Sierra master without servo. When I first put it on the road the pedal was a bit heavy with some premature locking of the fronts.

However, now the new pads and shoes have 'bedded in' the brakes are near perfect - much less pedal pressure required, no problems with balance.

In a nutshell - No Servo Required.