Yes, I have to say that was my understanding - a pig of a job.
I’ve just changed mine, or partially I have. I purchased the new one from MX5 parts not the Mazda one. I only had to change the stepper motor the valve was free. There are 4 screws holding them together, it was a fiddly job but completed for the price of the valve a few scratches to my hands and a few choice words. It took around 4 hours total to complete. Maybe a couple of hours if I did it again.