Thanks for the input folks.

I believe Dylansbob is right about those being Cook Bros cranks - there's a crack on the NDS arm unfortunately, which I understand is/was rather common. ​​​​​​
Pretty sure those are Mavic Wishbone/Y shifters, and are meant to be mounted under the bar (the cable exit angle sure seems awkward in the current setup).

If I'm interpreting T-Mar's serial number guide correctly, it looks like Scott frames were being sourced from the same builder/factories as Jamis & Novara at the time, so all these seem like viable possibilities. The specific combination of that pointed lug/fast-back seat cluster with TIG-welds everywhere else seems a bit elusive, Google image search-wise at least. Any other telltale indicators I might be overlooking?
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