power brake booster questions

getting ready to do my power brake conversion on my 70 duster. couple of quick questions.

1. at idle, i have anywhere from 11-15 in of vacuum. it isn't stable, but i believe that that was due to my testing equipment. using my mityvac as a gauge, and the manifold vacuum port on the front of my edelbrock carb. the other is timed, and at just off idle reads 15-17. should i pull the plug on the back of the base of the carb and test again with the distributor vacuum advance working, or is this accurate enough? also, will this be enough vacuum to operate my brakes correctly?

2. is there any way to test my booster on the bench before i restore it to make sure its still good? my mityvac just doesn't pull enough vacuum.

3. there's two ports on the check valve. the bigger goes manifold, but where does the little one go?

4. would it be OK to run this setup without the brace to the fender? i really don't want to drill holes if i don't have to.

5. the manual brake cars and the power brake cars used the same pedal, right?

thanks
Michael