A short shifter that has not been discontinued! Your R154 most assuredly needs a shorter throw shifter, as that truck transmission has never been speed shifting friendly.
This is specifically for R154 transmissions, but may also fit similar models like the W58, R150, R151, R155, etc. We only have confirmation on the R154 so far. Please be aware it may take a few days to a week to have this ready to ship