'03 379 cab a/c

My front a/c keeps freezing up pretty easily every 90 minutes or so, when I shut the compressor off and switch to outside air feed it thaws in a few minutes then repeats. Even though im getting good airflow im thinking about the coil, core...whatever... in the dash needing blown out because the sleeper a/c is not freezing up also.

How hard is it to get to and are there any little tricks or things to watch out for.

How big and long of a job is this? All afternoon better done at home or can it be done in a hour or 2 in a truckstop parking lot?

 

Turned out that the low psi switch was broken off.