duster 727 update and help needed

hi Guys , new trans works ok in 1st , wheels are turning but the 3rd manual 'stick-shift'and reverse gear is not working when we put the gears into them ...what can it be ? 727 with red clutches and new stall converter , kickdown system , not reverse valve body

Do you have a race shifter in the car with a cable ? And if you do , do you the correct shifter arm that came with the shifter on the transmission and cable adjusted correctly ?