if you down mk4 5 speed route youll probably need a flywheel and clutch too ive found the mk5 bellhousing to be smaller than mk4 ...the hard way
i bought a clutch for my mk5 gqq and was sent a mk4 clutch which stuck out too far locking up the engine/box and my starter basically abliterated...
you can do a delete mechanically or with software
no matter what the ecu needs to be flashed to turn off the eml
cant do it with vcds ,it wont limp mode
if you had mpps or similar i could egr delete youre ecu flash for you (y)
seen white smoke caused from one cylinder being down on compression before ,although you could hear it slightly in exhaust note at same time was one puff of smoke then cleared with other 3 cylinders firing