The 63 Galaxies, a 406 and a 427 car, that I ran did not have fan clutches. To my knowledge that area of both vehicles were factory original.
I have a few 1963 Galaxie window stickers for 427's, they do not call out anything HD, including brakes, springs, or cooling. The window sticker from my 1961 390/375 HP car only calls out FADE RES BRAKE LINING, HD FRT-RR SPRINGS SHOCKS. However, all of them call out HI PERF engine.
The "1963 Ford Facts Figures for High Performance" booklet calls out both fans for the 406, but for the 427 it states "Part numbers not available at time of printing. All parts available Feb 15, 1963". Perhaps a later revision of this may clarify this.
In the Ford 1963 Police brochure it is listed as an LPO (Limited Production Option) a Extra-Cooling Viscous Drive 1.25 Ratio Fan for the 352 V-8 and 390 V-8's only. Perhaps it was an LPO for the 427 also.
In the 1963 and 1964 Engine Equipment Assembly Manuals it calls out a "1.25 Extra Cooling Option" and use of a viscous slip fan drive. This was available on either a generator or alternator equipped car. However, again this is only for 352 and 390.
BTW, the only termonology I've come across in Ford documentation from the early 60's is either Standard or Extra Cooling. I don't recall seeing the term HD cooling used in any Ford documentation. Do you have any Ford documentation from 1962 - 64 that uses the term "HD Cooling"?
It's difficult to even say if a 1963 or 64 Galaxie with a 427 ever left the factory with a fan clutch, unless there is a specific call out in Ford documentation. With a 45+ year span it's difficult to say what is and isn't, particularily on a restored vehicle. To go by parts books is uncertain, because in some/many cases what was used in service does not accurately reflect what was used in production. I have a couple of other places to see if anything else exists on this subject, but nothing that I will get to immediately.
The only 427 Ford that I know for certain that was delivered with a fan clutch was the 1964 Thunderbolt Fairlane.
If there is any other documentation related to this subject, I would be interested in seeing it.
