1.6HDi (DV6TED4) pressure regulator

[freddyokel]

I've got a DV6TED4 1.6HDi (110bhp) in my 207cc and I'd like to swap out the pressure regulator on the high pressure fuel pump.
The regulator is at 90 degrees to the pump drive shaft and held in with 3 hex head bolts but I can't work out how to get access to it.
Shoving my hand down the back of the engine at the cambelt end, I can feel the regulator but no chance of getting a tool in there.
Is there a known way of doing this?
My current train of thought is to remove the battery, the intake plumbing and the airbox to gain access from the gearbox end of the engine.