Can someone stop Tom multiple posting!
No idea why that has happened, must be the work internet as only clicked it once!
You mention a new loom that came with the pump and are asking about the outside connector on the car's loom I assume. That means you have a new bulkhead connector for the fuel pump housing. That's a Delphi multipack 150/280. On the outside it's a straight metripack 280. I don't think 280 pins fit the old metripack 150 connector that's on the loom of the car, so you have to change the whole connector to a metripack 280. You should be able to source that from the likes of RS Components and such. Issue with these connectors is that often you have to order them in components: the connector itself, the pins, the weather seals and the weather sleeve. Some places sell them as complete units, which makes ordering a lot easier. The connectors are pretty standard and widely used.
BTW, if you have upgraded the pump, you might also want to check the wiring. The power wires are not really designed to take much more abuse then from the OEM pump. When you're at it, upgrading the power wires is not a bad idea.
Wow, exactly what I was looking for! You are exactly right, the connector I want to replace is the old square one on the loom side as the new pump uses the newer connector. I was scrolling through the RS site but wasn't sure on the size. The new pump has a lower draw according to Gaz so I'm not especially worried about replacing the wiring.
For reference, my standard (old) connector shows no signs of corrosion, shorting or heating up. In face, inside the seal the plug is very clean.