Ok so i deceided to go down the machining route to try and save some $$, dont want to over capitalise lol.
Took the drive plates over to a mates place and let him work his magic.

Making sure the plate is a central as possible in the lathe using a dial gauge (precision instuments these mowers :))
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Maching
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All done, took 0.5mm of the forward plate and 0.3 off the reverse plate.
Could have gone more but didnt want to remove too much material.
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