I'm running an externally mounted Fuelabs in-line pump fed through a pair of Holley Hydra Mats. It's a two speed pump with the higher speed being triggered via a micro switch on the throttle linkage that triggers when the outboard carbs are opened.

They have some really nice pumps and most have a two year warranty. Mine is super quiet on the low speed circuit, and fuel pressure remains constant at both low and high speed. I do run a return style system.

Worth a look if you are shopping for quality fuel pumps.

https://fuelab.com/

Also, these guys were very knowledgeable and helpful in getting my fuel system properly set-up and sorted out. They also have various sizes of fully submersible fuel line.

https://www.harmonracingcells.com/