Don't overdo the tension on the belt. Fords ran fairly loose.
One thing you can do to improve it is to replace the cut out switch on top of the generator with one of the solid state units from Mac's. They had one that also acted as a regulator. Only proviso is if you boost the vehicle with 12 volts, you automatically fry it.
Edited to add: I don't see them on Mac's site anymore, but here is a site with them:
http://www.funprojects.com/products/10505v.aspx
170 in the winter is fine.