Do you have a halyard and a sheave at the top of the mast? Aka a pulley at the top of the mast and a rope to haul up the sail?
The old town lateen is the same as a Sunfish lateen- look up videos for sunfish rigging.
It helps to have some way to tie off the halyard, I just tie mine to a thwart up near the mast. I recently added a small thul pin on my mast seat to tie off the halyard, I can post pictures if you’re interested.
One innovation that people use with sunfish is they put a cleat on the mast, that way the tension of the halyard line is not pressing the mast down into the hull of the boat. You still have to cleat the line off to the hull so the whole sail mast and rig are still attached somehow.