~Update~
Interesting. I see they list a 8620-B belt for 56 with a 4 bladed fan. Problem is though I see two different part numbers for the fan belts for '56. First one is a B6A-8620-A with markings on the belt of ECG 8620-C. Then the other one is C1TZ-8620-C with belt marking of B6AE-8620-A listed as an optional belt for high speed 97:1 water pump pulley and 4 bladed fan. That sounds like the one for mine as my Fairlane has the 4 bladed fan not the 3 bladed fan.
I need to email Casco and ask them what markings are silk screen printed on the belt. Hopefully its B6AE-8620-A but looking at my book there were a lot of different markings for belts based off what amperage output generator you have and if you have ps or not and if you have a 3, 4 or 5 bladed fan.
OK... Let me see if I can add my usual confusion to a subject ...
The BELT CHART in the FINAL ISSUE 49/59 is confusing in that most original service part numbers have been superseded and causes confusion. There is (was) a ROTUNDA BELT & HOSE CATALOG which made the whole thing much simpler.
The C1TE they are offering was a 1961 PN that superseding the original PN (both ENG and SERVICE PN) and that should be found in a period correct 1956 CHASSIS PARTS CATALOG. You also have to ask what manufacturer they are using for the replacement belt. Be heartbroken (IMO) to buy one and find MADE IN VIETNAM on it.
And here just for aggravation-
https://autopartsobsolete.com/1956-Ford-Ford-truck-Nos-fan-belt-b6a8620-a.htmlAnd also remember that SERVICE REPLACEMENT PARTS may vary in appearance form ASSEMBLY PARTS.
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