My brother, a TR4 owner, decided to take my 6 for spin. He hopped in, cranked it up, pushed in the clutch, and then, assuming the shift pattern was the same as his TR4, he pulled UP on the shift lever, intending to then push it to the right and back. Instead, when he pulled up, the shift lever pulled right out of the linkage. I have removed the shift console cover so that I can reconnect the shifter. The shift lever is splined at the bottom but I see no way, e.g., a set screw, to fasten it more firmly to the linkage. Am I missing something?