Turns out the eprom is a surface-mount 27C1024 so I'm not messing with that - I don't have the gear to remove and re-fit it. Bottom right with the sticker on it.
However, having realised I have almost all the parts needed to do the manual swap I put the original manual ECU number in to ebay for a laugh. One available, in Lithuania, for £100 delivered!
Er, yoink!
So, if anyone reading the thread is pondering buying this when its done, you've got two weeks to get in touch and let me know whether you want it manual or automatic
In the meantime, I'll be working out how to make my clutch pedal solution work with the PF's accelerator cable...