While driving the Model A today I went to shift from second to high gear and its stuck in second gear. Got an 8BA flathead with a 52 top loader three speed from a pickup (open driveshaft). This never made any strange noises and never has in the 1200 miles that this combo has been running. Popped the top off the trans and cannot pry it out of second with a couple of large pry bars. Don't want to get too rough with it. This acts like it over shifted and will not come out of second gear. Any ideas what could cause this problem?