Ok- this may sound harsh but not meant to be. I am trying to save you some heartache and money.
Why on earth would you go through the trouble, time, and expense to build a 347 and leave stock heads on it. You will be VERY dissapointed. There is NO reason to build a stroker motor unless you plan on getting a good set of heads, cam, and other supporting parts. Just do a stock rebuild.
That being said, a set of GT40 heads on a 347 IMO will be a dog. You need at least a set of AFR or TFS 205 heads and either an Ed Curtis custom cam or a tfs stage 3 or comp cams extreme cam and matching valve springs.
Right now, you have a bunch of mismatched parts that will produce a lousy combination. The intake is a choke point for a 347, the injectors and throttle body are too large, and I bet that is a C&L Mass air.
The first thing you need to do is determine your budget and goals. Expect to spend around $4-5000 for a decent 347 build. Too much? then save up. Then realize with all that new found power, your transmission, cooling, braking, and
suspension need to be upgraded. Actually, the first thing I would do is get rid of the 3.08's to at least a 3.55 gear.