Wondering if someone who has replaced their wiper motor previously can let me know if the dash gauge cluster assembly needs to be pulled to replace or if it can be done from under dash? Thanks.

 

It's done from under the dash but you need to be a contortionist.
The hardest part is removing/installing the clip that holds the linkage to the arm on the wiper motor.
Also, note the position of the arm on the motor. It can go on two different ways. If you get it 180° out, when you turn the wipers "off", they will park in the vertical position. You don't want to have to do the job twice.

 

Thanks mike!

 

 

You can also remove your wiper arms, and then unbolt the 'stub shaft' assemblies from the firewall, along with the motor, and then have better access for connecting the transmission linkages to the new motor.

And take plenty of pictures of what you've got before you disassemble anything.
Here's a reference picture I took of mine when I did my cab swap:


The picture worked for me, because only after I got it all back into the new cab, did I notice that the transmission arms are marked "Left" and "Right." And it all worked the first time. I was lucky and already had the dash out for this...