Arfie,
what seems to be the problem with the tacho?
Personally and after having received the prices from VP and VDO (who apparently manufactures the instrument for VP), I decided to open yhe instrument, produce an o-ring of sorts and reassembled the tacho; seems working fine, but the problem was of course mainly aesteical.
Cheers,
Gianenrico
My VP dealer said that they're prone to not worknig if they get damp (sic)! I'ver put mine in the airing cupboard for a month or so. aslo you can get a signal booster from VP. a new one cost around 180 quid.