Just a suggestion.....your electric pump can be put on a "momentary" push button switch and used as a backup for supplimenting your mechanical pump in the event you have issues with E10 fuel. That's the setup I've been using to overcome fuel pressure loss caused by engine heat soak.
Secondly, it wouldn't hurt to regulate the fuel pressure from your mechanical pump. I'm running a dual carb setup with an inexpensive Mr. Gasket adjustable regulator and 3-1/2 psi at the carbs is adequate. If the PO was having vapor lock (phase separation) issues I'd also suggest you make sure your steel fuel line doesn't sit too low between the valve cover and thermostat housing. It might not look "cool" but neither does a truck with the hood up cooling off the engine compartment so that you can restart the engine. This is where the momentary switch on the electric pump will force cool fuel through the line and the engine will refire. Hope this helps.
Dave
