I would also definitely send a lens like that out of town to someone with lots of experience opening, reassembling and collimating such lenses, and who has all the equipment to do the job right.
I would trust Don Goldberg at DAG Camera Repair (Wisconsin) and John Van Stelten at Focal Point (Colorado). I have used both with great results. If you would like the "feel" of the lens tweaked at all (stiffer, looser, clickier or less clicky aperture ring), Don is very good at that.
When working with Don, I think it is imperative that you call him first to confirm he can take on the work and establish the time frame for completion (also to establish rapport). Send the lens with a cover letter repeating everything you confirmed in the phone call, and call to confirm receipt. Then call again about a week before it's supposed to be ready, and maybe again if necesary. Assume Don does not read his email.