We decided a centred installation would be best - it is easier to install (you can use the rudder to get a true vertical alignment), plus we felt that whilst you can install off centre the boat would perform better with the main rudder and Hydrovane rudder in line.

We didn't realise we would have to remove the ladder until we went to drill the second hole in the bottom bracket - the first hole went in fine, but the second fell right behind the ladder so we couldn't get the drill in!

Fortunately when we put the ladder back in the same place it cleared the Hydrovane unit by about 1/4" so is fine and still perfectly useable - we were fortunate that the stand off brackets on the ladder were so deep to allow the Hydrovane bracket to sit behind them.

Jonny