fan clutch

What height do you need? Hayden lists several.
Ecatalog
Hayden is generally accepted as one of the better ones out there- available at most retailers.
https://www.rockauto.com/en/moreinfo.php?pk=1793688&cc=1086982&pt=6812&jsn=544

One thing though; non-thermal fans are generally not considered heavy-duty- by nature they are less efficient and shorter-lived. From Hayden's own website:
Non Thermal