There is research being done on it already, but some of the records aren't online and it may take a visit to the National Archives in England to get them. Also other records have been found in America for a Captain James Lockhart which may include his early service record.
Could the request for help be held off for this profile until the new research can be verified? Nae, myself and a few others are actually working on this in the background. It may turn out to be a very complicated profile. To put it in cotext this profile has been a several decades brickwall.