An apparatus comprising: a needle bar shifter of a tufting apparatus, the needle bar shifter having first, second, third, and fourth shaft segments, each of the first, second, third, and fourth shaft segments having respective first (14,20,26,32) and second (16,22,28,34) ends, the first and second shaft segments being aligned and spaced apart in a longitudinal dimension, the third and fourth shaft segments being aligned and spaced apart in the longitudinal dimension, the first ends (14,20) of the first and second shaft segments facing one another, the first ends (26,32) of the third and fourth shaft segments facing one another, the third and fourth shaft segments being offset from the first and second shaft segments in a transverse dimension that is perpendicular to the longitudinal dimension; and a shifter adjustment assembly configured to couple to the needle bar shifter, the shifter adjustment assembly configured to cause adjustment of a position of a needle bar of the tufting apparatus relative to a hook bar of the tufting apparatus in order to maintain a select positioning of needles of the needle bar relative to respective hooks of the hook bar, the shifter adjustment assembly comprising: a first body that is configured to couple to the first ends (14,26) of the first and third shaft segments; a second body that is configured to couple to the first ends (20,32) of the second and fourth shaft segments; and a coupling between the first body and the second body, wherein the coupling is configured to releasably secure an axial position of the first body with respect to the second body along the longitudinal dimension, wherein the first body and second body define respective complementary surfaces that are configured for sliding engagement so that: movement between the first body and the second body in the transverse dimension is restricted; and movement between the first body and the second body in the longitudinal dimension is permitted. a needle bar shifter of a tufting apparatus, the needle bar shifter having first, second, third, and fourth shaft segments, each of the first, second, third, and fourth shaft segments having respective first (14,20,26,32) and second (16,22,28,34) ends, the first and second shaft segments being aligned and spaced apart in a longitudinal dimension, the third and fourth shaft segments being aligned and spaced apart in the longitudinal dimension, the first ends (14,20) of the first and second shaft segments facing one another, the first ends (26,32) of the third and fourth shaft segments facing one another, the third and fourth shaft segments being offset from the first and second shaft segments in a transverse dimension that is perpendicular to the longitudinal dimension; and a shifter adjustment assembly configured to couple to the needle bar shifter, the shifter adjustment assembly configured to cause adjustment of a position of a needle bar of the tufting apparatus relative to a hook bar of the tufting apparatus in order to maintain a select positioning of needles of the needle bar relative to respective hooks of the hook bar, the shifter adjustment assembly comprising: a first body that is configured to couple to the first ends (14,26) of the first and third shaft segments; a second body that is configured to couple to the first ends (20,32) of the second and fourth shaft segments; and a coupling between the first body and the second body, wherein the coupling is configured to releasably secure an axial position of the first body with respect to the second body along the longitudinal dimension, wherein the first body and second body define respective complementary surfaces that are configured for sliding engagement so that: movement between the first body and the second body in the transverse dimension is restricted; and movement between the first body and the second body in the longitudinal dimension is permitted. a first body that is configured to couple to the first ends (14,26) of the first and third shaft segments; a second body that is configured to couple to the first ends (20,32) of the second and fourth shaft segments; and a coupling between the first body and the second body, wherein the coupling is configured to releasably secure an axial position of the first body with respect to the second body along the longitudinal dimension, wherein the first body and second body define respective complementary surfaces that are configured for sliding engagement so that: movement between the first body and the second body in the transverse dimension is restricted; and movement between the first body and the second body in the longitudinal dimension is permitted. movement between the first body and the second body in the transverse dimension is restricted; and movement between the first body and the second body in the longitudinal dimension is permitted.