I am amazed that there are so few options in Seattle! In Portland, which is hardly a hotbed of Ferrari activity, I can think of three shops off the top of my head who could do a competent PPI on pretty much any Ferrari. There are probably others as well, but the three I am thinking of I have personal experience with.
I suppose some of the local restorers, like Dennison or VRM, could do it. Problem is, could anyone get them away from their bigwig clients to work for the little guy? Carlo is the most accessible and trusted expert to us mere mortals.
On a similar subject, I bought a set of new tires for my Dino from Coker. Who would you trust in Seattle to mount them? Years ago I used Trueline near Jackson because Grand Prix/FoS recommended them and did a good job, but things could have changed.