Hello Sam, welcome to UKGPL.
These are the links for the 65 mod-
David Wright's 'Legends' site
http://fp.gplegends.plus.com/ has the download of the most recent 2.0.1 version (under 'details') as well as being an exceptional guide to both 1965 and 1967, for those interested in Formula One history.
Unfortunately the current 65 mod download does not have default setups. Default setups can be downloaded from
http://www.neurology-crew.com/gplserver under '65 setups'.
This thread
https://www.simracing.org.uk/smf/index.php?topic=4827.0 might help with the installation of Gem+/Igor which is needed for both online and the 65 mod, it has its own internet site
http://gem.ebi-service.de/To register for our 65 Novices races just post here
https://www.simracing.org.uk/smf/index.php?topic=5133.0 and vote in the poll. You'll notice that there are several options asking how much you want to race. If you want to try the 67s the introductory level is the Clubman's Cup. The Novices run on alternate Tuesday nights and Clubmans on alternate Sundays, the schedules are at the top of the registration threads.
If you select a night to make a connection for some online practice message me on this site and I'll try to be online to help out. It's best if you don't attempt to make your first connection on the night of a race!