Yes, I came up with N5661G as well. "N" numbers were assigned in blocks, so It's not hard to figure out, using serial numbers before and after the one in question! The problem is N5661G no longer shows up in the FAA database as a Cessna 150! It was "deregistered" to the original aircraft, and is now reserved for another aircraft. FAA archives are organized by "N" number, not serial number. Requesting information on N5661G will now draw a blank!
There is no easy means of finding the original history for N5661G, except maybe through the freedom of information act, and then only if the previous information is archived in the Library of Congress.
Your link shows s/n 15071161 as N311SG... same as the FAA database!
