1969 Grand Prix SJ - Rear End GEAR RATIO Options

You could look in a 69 factory shop manual, or if you order PHS documentation you'll get a copy of the 1969 Grand Prix order sheet and that will show it. There is a table in the shop manual that shows what the standard ratio is for every kind of car. I included my shop manual when I sold my 69, so I don't have one now. I just vaguely remember that some of the slow speeds were 3.36, 3.55, 3.90, and 4.30. They didn't use 4.11. You are a lucky man to have a 69 model SJ.