Welcome to the site.
What year 150? If it's a later build 150, the certification label in the drivers door jamb would have the axle code (if nothing has been changed out)
If correct ratio is in question, another way to figure for ratio w/no tag, is to raise the axle and mark the axle flange location,, rotate the input yoke and count complete turns and partial (clocked) to make the axle rotate a full revolution to your mark.. Depending on MY, axle/gearsets would be a guess...
Last edited by Hayapower; 03-15-2017 at 02:02 PM.