Paul,
I have seen a v8 Bristol (a 412) fitted with an electric fuel pump which was simply used to prime the carburettor before starting, after that the engine used the original mechanical pump.
This was because if the car had been standing for a while one would have to crank the engine a fair bit to allow the mechanical pump to pull sufficient fuel through from the tank. It's possible this was more of a problem here in Australia with our warmer weather which may have resulted in a vapour lock.
Before the use of reduction gear starter motors became commonplace it was reasonably easy to flatten the battery before the old v8 would start!
I just thought I should mention this in case this is the way your car is configured. Obviously if the mechanical fuel pump is no longer there then you're just running on an electric pump
