Like the subject says, the 5 speed shifter of my 92 mighty max is's the skinny...

About a month ago, my shifter suddenly had excessive loose play in it. A
week ago, it started failing to go into reverse (3 times)...then 2nd
(twice). The last time, it stuck in 2nd and will not move into 1st,3rd,or
5th (the gears on the top of the shifting pattern.) and it will move
loosely left and right. I pulled the boot back and found the top shifter
bolt was missing and the other two were loose.

I first need know the exactly size and thread size of that missing bolt
(it's not in my haynes manual) so I can replace it. And I need to know if
there is an easy answer for what might have my shifter the way it is now.
Can I do something working through the shifter hole if I take the shifter