no ive got the same main pump as you mr phil! and the holley lift pump i had a look through the litriure of the pump and it didnt say anything about needing to be fitted at the same level as the tank!
Should be fine with the lift pump as this will draw the fuel to the main pump rather than it having to suck fuel from the tank. His swerl pot (sp) takes the fuel level higher than the main pump giving it gravity feed.
yeah, I thought it was only high pressure pumps that had to be lower? hence the 'lift' part of lift pump? I hope thats the case cos I don't want mine under the car getting covered in shit!