I have the electric fuel pump above my tank, rt hand side on the Kirkham.
I get about 7psi with it on and 4 - 6 with it off. I have had fuel starvation with just the mechanical at higher speeds too, which reminds me to turn it on.
I added an electric fuel pump to my Classic Roadster years ago to prime it if I
hadn't run it for awhile. It would take forever for the mechanical to bring it forward. Now if I haven't run it for awhile I let it turn over until I get
oil pressure,
then stop and turn on the electric pump and listen for it to slow down when it
gets pressure (it stops - cheap kind). Then I just pump the gas once and it starts right up. I also do the same basically with the Kirkham, to pre-
oil it.
So far so good with that strategy. Priming the CR was a big help. Both electric fuel pumps are toggle switch operated.