do your self a favor and stay away from edelbrock carbs. if your gonna go the afb style go on ebay and find a 625 carter afb competition series, theyre bullet proof but they stopped making them about 8 years ago but guys still have them new in the box for sale.
i personally would get a base plate for the holley you have; theyre so versital and easy to work on. it will work good on a 318 and a 360 if your not gonna turn anything over 6000 rpm.
put in a 68 jet in the front and a 74 in the rear with about a 7.5 power valve and that 318 will be happy. bump it to a 71 and 78 when you go to a 360, if you need a little more flow just get a quick fuel center body it
thats my thoughts