Knowledge is power, now you understand the insides a little better up
Try using a flat bladed screw driver or another lever to see if you can possibly disengage the 3/4 slider from third gear scope
Don't get real aggressive on prying on it though tsk
I have made them stick on a early Ford tranny when speed shifting and had to remove the cover to get it to disengage wrench
Good luck, maybe you should fix it yourself work twocents
There not really hard to work on work scope
Good luck up

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)