Currently re building a pair of Gen 6 502 efi. they actually started their life as a Volvo 8.2 unit. since then many rebuids and bottom end components changed before I have got them. So they still run the standard low pressure fuel pump with cooler fitted to the rear of the engine, I want to junk this unit and replace. they have ANSU matched injectors, MSD ignition with marine 6M-2L boxes. Holley high pressure fuel pumps. What can I do to remove and replace the old low pressure fuel cooler unit ?
Thanks

post a pic of what you are wanting to remove, Im a little confused

How can I get pics on, I will take some of the unit fitted to the engine. So I have a holley fuel pump bulkhead mounted then in the attached parts view bellow I have unit 20-21 on the rear of the engine. Which I want to replace?

Part Sections: Fuel system and lower intake manifold - Volvo Penta Shop

That diagram seems to indicate that #20 is the high pressure pump, not low.

Sorry yes. High pressure with fuel cooler.
seen rear of engine here

the water fed ends and inside is getting corroded, pumps are years old. from stripping one engine I just caught a piston going bad with lean signs on the edge of it.

Volvo seems a bit different than Mercury, but most remove the pump and regulator and replace with after market like Aeromotive so such and run a return line to either the water filter head or filler neck of the fuel tank, you can hook the wather hose together with some kind of coupler pipe

Thanks. Is it just as easy as find out what pressure the standard pump runs at. And find an after market of the same ?
The Holley infront of this must just feed that pump from fuel tank. Low pressure

that correct the Holley is a lift pump that feeds the high pressure pump that feeds the EFI rail, yes Id get a replacement pump and be done with it

Do you know what psi or litre per hour is needed for these ?