If you'd left the induction system stock it probably wouldn't have killed the filter/hydrolocked you could have an argument on your hands unless RAC had previously approved it as a modification, good luck.

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Beaten up old 98 Gen 2 Liberty, 13.0, stock V3 STI running gear.
07 Transit motor home
69 VF & 70 VG Valiants needing full restoration
Yamaha Zooma 50cc rocket hopefully going with the Transit.