Hmm, the PLA can have about 0.3 to 1% shrinkage, which my explain tightness in the long direction.
But i re-measured, and it seems that the model has small error too.

From the model: inner length = 127.34079 measured from print 127.2
phone 127.75

inner width = 65.443081 measured from print 65.3
phone 65.0

I just ordered some Premium PLA 90 from Orbi-tech. Lets see is it any better, color selection is poor for 1.75mm (3mm better)

I think i have asked, but what cad do you use? possible to share originals under DWTFYWT-license ? or just for me, i'll buy you a beer or ES