Outrageous Upgrade

I'm so annoyed, I could spit.

A few years ago I purchased an Eye-One spectrophotometer outfit, which includes the hardware device plus software. I have used it extensively to profile my monitors, projectors, and of course to make printer profiles.
For the past couple of years I haven't used it much, if at all, because I have pretty well standardized on a couple of papers, and am still using the same printers. I'm neither a profiling hobbyist nor a professional profiler. Simply a fine-art photographer who enjoys having custom-made paper profiles.
But the other day Epson sent me their first new printer in several years, the Surecolor P600. After setting it up and making some prints with provided Epson papers, I wanted to do more rigorous testing, and especially a comparison with my Epson 3880, using Canson Baryta Photographique, my preferred paper. At first I downloaded a P600 profile from Canson, but it was off.  So I pulled out my X-Rite Eye-One Spectro to make a new profile for the P...