1986 Ford F-150 transmission

First try linging up the shifter. There is usuyally a hole in the cnter between the shift plates when put into neutral that can have a screwdriver or drill bit put through to line up. Then adjusat the arms to line up with the shift arms on the outside of the transmission.
If you have to go further, Note near neutral possition of the shifter fork arms on the transmission. Check the shifter to see which fork is the 3-4 and remove cover. Then adjust the shift fork arms with fork in neuatral postion and get as close to neutral on the fork arm as possible. Put cover on and move the fork. See if it feels like it is going into gear and check input output to confirm. Also make sure it does not go too far into gear.