Need help a.s.a.p please.

View attachment 1715512008 My 727 transmission in my 1971 duster won’t shift when I’m trying to manually shift it with the shift lever under the car but when I dropped the throttle body it shifted just fine when unbolted from the transmission, then when I bolted it back it wouldn’t shift through the gears again??? I’m trying to see if this rod might be the problem, does anyone know what this rod is, I attached a pic. Also if anyone has any suggestions I would really appreciate it.

Also a side note: The tires went around freely when I had the rear end jacked up but when I put the throttle body back in the tires will no longer move and still no shifting with the lever, it just seems frozen.