Hayden nylon/plastic fan blades?

[Des67Spl311@aol.com]

Hi all,

I have a 1967.5 SPL311  1600.  I have an intermittent heating problem.  At 
the last Bay Area rally at DatsunMike's house, some folks were discussing 
Hayden fan blades.  Does anyone have the actual model number of those Hayden 
fan blades that will fit the '67.5 1600 engine? Likewise any comments about 
their effectiveness is also appreciated.

Thanks 
Des