Yes the S3 gearbox will bolt up to the ABF block. (done so myself)
You will not be able to use the flywheel/clutch from the ABF.
You will need the dual mass set up or buy an after market solid flywheel.(done this also)
The ends on the cable shifters are different so would be much easier to change to the MK4 golf, S3 and any other model shifter that come with the o2m boxes.
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