The seller confirmed our fixture drawing before purchase. The delivered FR5 has a different suffix and a visibly different fixture-alignment interface. Thirty-two days waiting, tooling still unfitted. Their equivalent answer has no comparison behind it. I need the configuration explained before this turns into our workshop modifying parts to rescue the order.
Send the confirmed assembly and delivered identifiers together, with views locating the visible difference. Ask for the delivered interface drawing and a feature-level comparison. The different suffix might be meaningful or administrative; the visible interface change needs its own explanation. I wouldn't machine your fixture to suit a photograph or assume a new adapter is harmless just because it makes the holes line up.
They have sent a drawing carrying the delivered suffix. No comparison with the configuration they confirmed, and it doesn't explain the visible shoulder around our alignment adapter. The installer is checking what that drawing actually identifies.
Good to have something identifiable, but ask them to answer the shoulder difference directly. Also ask whether the original confirmed configuration is available. That gives purchasing actual alternatives to consider, without declaring the delivered one unusable before the technical comparison is done.
Both questions are back with the seller. No acceptance of a substitute and no fixture alteration authorised. I'll post when the installer has a comparison we can actually discuss, rather than another model-name assurance.