Update O/D Off Light Flashing
OK, I finally got a chance to work on this. I changed the valve body, trans filter, and the low/reverse servo (because it had to be removed to change valve body). Added new fluid and it seems to be shifting fine. O/D off light has not come on. I don't know for sure which part fixed it, but if you have to change the valve body, you might as well change the trans filter, the low/reverse servo and add new fluid. Hope this will help someone.