Driveshaft Center Bearing Diameter?

[LorenS]

I have read the FSM for changing out the center bearing on my 2-piece driveshaft, and looked in the Parts List in the Articles section (which is for 2001/2002).  Part # listed is:  04773014.  When I go to Rock Auto that part number isn't listed for 2001 models, just 2002 models.  For both years, they list options with two different diameters (even when I've selected Diesel and Auto, etc.)  1.5748" and 1.3780".  Is there a good way to determine which I need without removing the clamp for the rubber boot and putting calipers on the shaft?

 

EDIT: The difference is in the Wheelbase.  If you have a 138" wheelbase (Quadcab, shortbed), you get the 1.3780" bearing.  If you have 154" wheelbase (Quadcab, longbed) you get the 1.5748" bearing.  Of course neither RockAuto nor other parts retailers care to mention that difference - THANK YOU @Mopar1973Man and your staff for compiling and sharing the parts lists, etc., to aid the rest of the community.

Edited October 22, 2019 by LorenS
Answered my own question!

[Mopar1973Man]

Exactly what you'll do. Pull the clamp, slide the boot back, measure with calipers.