After all the talk (6 months on this thread), I finally pulled my engine out and replaced it today with a 2.5 - I've attached a piccy - so if anyone can identify the new lump for me - that would be a start! Hopefully I haven't made a serious mistake with the purchase.

The gearbox that the letters 'VT88' stamped on it, so If anyone has any comments on what the hell I've just stuffed in my van, that would be excellent!
I still need to attach everything (including the cross member & prop) which I still have to find, and I seem to have a load of wires that don't connect in the same way that the previous engines wires did.... but aside from that ... it's getting there. Thanks to everyone that replied to my previous posts which gave me the confidence to tackle this thing in in the 1st place!