I remember talking to Allen Cross about this years ago, and he said the seal was FE only as far as the years 69/70 are concerned.
Since that time, the cars I've seen concur with that.
I have an NOS seal C4DZ-16A238-A, and it's approx 34 11/16" long, as well as a used one with staple holes.
AFAIK, there's only one version, so any chopping shorter would be done on the line.
The clips used elsewhere than San Jose are just common electrical clips.
I remember posting about them here a long time ago, and all of a sudden they were showing up on eBay for way too much money.
I guess somebody trolling here is slinging parts.
They're in the AMK catalog olive drab B-13428 or olive drab with half rubber covering B-10726 for a couple of bucks each, so don't spend too much people.