[Bullitt95]

The fuel could be spraying out between the regulator and the fuel rail. Did you check if the rubber o-rings are in place and seated properly? If that's not where it's coming from when you have the BBK regulator in place, the fuel will be coming from the gauge port at the back. Did you use the threaded plug that came with the regulator? My BBK leaked slowly from the gauge port even after I'd threaded in the plug but I cured it by applying thread lock/sealant.

 

[Bullitt95]

With the idle at 2500rpm, you definitely have a vacuum leak. The question is where from? The answer is to check every hose that's connected to the intake manifold, including the hose from intake pipe to valve cover. You may also have a leak from one of the gaskets between the lower manifold and heads, or between the upper and lower manifolds.
I still have the stock manifold but I ported both the upper and lower and have an FRPP 1/2" phenolic spacer sandwiched in between.