Ok Supra gang, to cut a long story short, years ago I put an 06 MEFI 5 320 MPI Indmar from a Malibu into my 04 SSV Launch. I purchased the complete engine less fuel pump bracket that has the bosch reg built into it. I've always struggled with maintaining 4 bar pressure with various systems using a Bosch 044 pump and ended up using a pressure gauge with an orifice and ball valve on the return system.
I now have retained the 044 pump (you can buy them anywhere and cheaper than a pierburg) and used an AC Delco GF822 filter/regulator that is commonly used in the US on various GM vehicles.
The whole reason I went with this was experimental and I could never get the OEM pump assembly in Australia. I had to buy a few -6 fittings but am extremely happy so far. Took it for a quick run this afternoon and never faulted. I do however intend to make a nice CNC bracket and change the layout, but I'm back on the water for the Australian Summer. I just thought I'd share this info as I'm always reading about fuel pump failures and it seems to be the weakest link in the drive train.
Attached are a few pics that may be o f assistance if you intend on doing the conversion.

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