Lark Tuning Guide
Designed in 1966 by Micheal Jackson, a designer of many Merlin Rockets and National 12's, the hull is 4.065 metres in length and has a total sail area of 17.15 square metres. It is currently one of the fastest non trapeze dinghy's around so having the boat tuned correctly is very important to stay competitive!
Below are several links to places you can find tuning and rigging guides
http://www.larkclass.org/images/media/Document/2008/Technical%20Documents/speedsail_tuning.pdf