I had a feeling that was the case with the new pump since carbs rely on pretty much a trickle fuel supply from a mechanical pump. At the end of the day, it isn't much for me to just pull the mixture control unit for now to replace what I need. I've just done the removal, and install process three times, and it's tedious. If I didn't have to do it again, it would be too soon.

The motor has just shy of 80K miles on it. I barely put 10K on it before it took the long nap, but the oil gaskets were pretty much shot when I bought it. That being the case, I'll eventually do a power train pull in order to completely overhaul the gaskets on the engine, and while doing that upgrade the cams, port the heads, etc. to get a little more naturally aspirated juice out of the PRV.

I'm just putting the feelers out there for what the options are, and I really do like the simplicity of Bill's setup in the engine bay, but at the same time I am still considering the EFI option. In hindsight, I wish I had a 5-speed.

Good luck with your LS swap. If I had a 5-speed, I was considering what it would take to drop a 2011-2015 Mustang 3.7 V6 in.