How to change fan belt?
http://www.automotion.com/1958+porsche+356+a/serpentine-belt-installer-tool.html - You may need one of these. From my experience, you'll have to stretch this belt over the pulleys.
Some Porsches use washers between the pully halfs. Removing washers moves the halfs together, thus causing the belt to run further out and thus tensioning it more. Just the opposite to loosen it.
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