i'm still waiting on pricing from weber.
i'll let you know when i get it
the weber kit includes an air cleaner which is matched to the carb top. yes the carb fits the edelbrock mani, given that the edelbrock mani is the one designed for the stock carb base:
Performer 2V 60° V6 Base #3785
Performer 2V 60° V6 Top (EGR) #3787
Top Gasket (included with top) #6941
if you have EGR, which i doubt, you'll need to go with 3787
crane sells kits with the cam,lifters,springs all together, and are reasonably priced:
http://www.cranecams.com/master/apps/chevy1.htm
look hard at kit #4, that'll be your best bet (without raising compression)
if you want to go with the comp cam, call them, they can get you just springs. the lifters will come with the comp cam.
the distributor i was looking at was actaully an MSD model with mechanical advance(vacuum advance). PN 8597. unfortunately, it must be used with an MSD ignition control.
in the early 2.8s, the only thing the computer did was advance the timing as the engine revs. in order to get rid of it, all you have to do is swap to mechanical advance ignition.
if you get rid of the stock carb, however, you must swap to the mechanical advance ignition, because of the throttle position sensor, which the weber carb does not have.
a great resource for all 60 degree v6 owners is
http://www.s-series.org/htm/performance/60degree.php
hope this helps a little