engine change?

[bullyd]

hi to all!!! tread from a desperate newbie:- i have recently bought an e34 520ise (m20) body work was mint and she sits on deep-dish 17s that look the bomb,needless to say i got a really good deal on her as at about 3500rpm the crank rumbles like a stadium of people stomping to 'Queens' 'we will rock you'. im not a rich man but have always wanted an e34 as my e28 was starting to bore me (ive gone as far as i can with her,shes a full M5 rep inc interior see pic). i am a keen home mechanic with a comprehensive tool box, i have been told that i can fit a 2.5 m20 lump straight in mine as long as i just plug in the corresponding ecu without changing the entire loom, does anyone know how true this is or even if a larger lump can be fitted without the dreaded loom change? also anyone know of a good, cheap, compatible engine for sale in the east anglia area of the uk? thanks in advance for everyones answers/suggestions.