While surely not the only one, in 40+ years into all this, I’ve seen this movie many, many times before with a lot of different parts for various vintage car makes/models, not just Daytona or Ferrari and also having been known to over-analyze/-think almost everything I get involved with, here’s my take, right or wrong, on these commonly available heater control/water valves: Like so many small parts or components used by various car manufacturers around the world throughout the ages, these too are/were made by some supply manufacturer who might’ve been making similar heater control valves for decades to numerous different automakers, just like a company called RANCO used to manufacture & supply heater control valves to many Detroit automakers throughout ‘40s, ‘50s, ‘60s &‘70s (maybe even later) and while almost all of those valves share same basic operating principles and many even look very similar, the one designed & made for ‘49 Hudson will not necessarily fit or work correctly into a ‘57 Studebaker or a ‘72 Plymouth. Or like KONI has been making and supplying shock absorbers to many automakers, including Ferrari, for decades and while the ones they designed/made as rear shocks for, let’s say SWB, may appear similar to ones they perhaps make for a ‘67 Aston-Martin or ‘78 Iveco truck or something, doesn’t mean they’re easily interchangeable. I believe the base problem with the valves being discussed on this thread is similar to above scenarios. There is/was one manufacturer who, perhaps for decades, made or has been making them with the similar overall appearance design and basic operating principles for various automakers, tweaking some of the features as needed per intended application. Now, decades later, after the OEM supply stock, including spares, that were made for some of the older Ferraris, including Daytona, have long been exhausted, someone, perhaps out of necessity, decided to adapt one or more of these, sort of similar looking valve(s) designed and intended for who-knows-what (maybe an Alfa or Fiat/Lada/Seat or Iveco truck or ???) to a Ferrari and next thing you know, word got around and all Ferrari parts vendors started selling this generic(?), “readily available” valve as a direct replacement, while everyone conveniently ignored the fact that it is not and may require severe modifications to make it fit/work correctly. It appears many owners or restorers, even if aiming their cars/jobs to be “Concours correct”, are just willing to accept & rig them for use “as is”, rather than attempting to rebuild the OEM unit(s), which can be difficult and time consuming. Heck, I wouldn’t be surprised if the factory Classiche department sells and installs these same exact valves as “authentic”/“authorized” for some astronomical fees. And I can only imagine (in disgust/horror) how many perfectly serviceable (correct) OEM valves or many other obscure/rare parts have been discarded by owners or service/restoration personnel over the years/decades.