I asked the same question on the TIVO Community Forum. A gentleman there provided a link to this thread
https://www.tivocommunity.com/threads/spectrum-and-cable-card.588503/page-15
It shows photos of a replacement Tuning Adaptor used by Charter Communications. It's apparently used in systems that have migrated to a High Split frequency allocation. Not clear if it's suitable for the Mid Split allocation used in Scottsdale. But if they have one for High Split it might be straight forward to build one for Mid Split.
