There are two potential issues.
The first one is the stock v6 fuel pump. Way too much pressure. The easy fix is to install a bypass fuel regulator like the Mallory 3 port. You adjust it down to 6 psi, 7 max, and you are in business.
Second issue is the integrity of the seam between the carb flange and the receiver. Easy to check with a bit of WD40 around the seam.
The Edelbrock is actually a little big for the motor. You may have idle issues with that volume of carb.
Call Edelbrock and find out if you need to adjust your primary circuit. The engine actually uses a little less than 500 cfm (487) max so your Edelbrock may be rich.
Actually the potential for a vacuum leak around the base is pretty high
[This message has been edited by Arns85GT (edited 09-06-2013).]