LOF and Reaglite date coded their material using a similar pattern. In the photo, the AS-6 code = American Standards (glass standards) level 6, and 6 was used for plastic windows. A '1' designation means it passed the steel ball drop test and could be used for windshields, a '2' means it didn't pass but is still usable for side glass. As you can imagine, a 6 designation means it didn't pass most any test except to keep wind, bugs and water out.
The other code is hard to read but it looks like 8N70 and if that's correct, then that - according to my research - corresponds to January 8, 1970 as the manufacture date.