So some clarification. In 1979 the tcase that connects to the L43 transmission does not have a neck down, but it has a shoulder to hold the coupler in place. Without that shoulder the coupler on the L43 can walk out. You can use a later model transfer case, but you would have to either still use your same input or use a sleeve or something that would prevent the coupler from walking. Marlin Crawler does not make an input that will work with an L43. The Total Spline input you are referencing is different than the L43 transmission input, neither have a neck down, this true, however the total spline runs the splines all the back on the neck, the L43 has the same length spline as any other input it just has shoulder where most have a neck down. Marlin Cralwer only makes Total Spline inputs for 23 spline, unless you're going to a 4.7 ratio, all Marlin 4.7 gears come with a Total spline input.
