look at genealogy under Manxnotebook for census details etc (also look under will summaries etc for much re Lonan) - however as you will discover by looking up Lonan in manxnotebook the marriage regs are defficient for the period you need for the parents - also no obvious will (and you will find summaries of most for the late 18th C on Manxnotebook)

Re visit - I'm sure you are aware (if not you will be on arrival!) that TT practice week starts weekend 25 May with TT week the week following - transport to the Island is both at a premium and at premium fares as this year is the centenary!