You have a 241 DLD that is a Light duty and a 241 DHD witch is the heavy duty. The difference's are the main shafts ,Pto drive option,Case's.
The 241 dhd has the PTO (power take off) option, a bigger mainshaft,and only 3 pieces make up the case's. It can have speedo drive or not.
The 241 dld has a smaller mainshaft, Can have pto option(I think only in 94-95 trucks) and has 4 pieces that make up the case's. It to can have speedo drive or not.
There is two different chain widths also but I can say what years,models had them and witch didn't.
Either of these t case's can be behind an auto or manual or in a 3/4 or 1 ton and it seem that dodge did this willy nilly as I can't see ANY pattern
Shift patterns are different 94-97 are one way 98-02 are another.
IKE