The best source of info on Guild labels up to 1977 is Hans Moust's The Guild Guitar Book. Altho' the book ends with '77, Hans himself is a member here, and is very gracious in answering questions.
There is some limited info and pics of some of the label variants on
Reverb... The following info is summarized from Hans' book, with pics I found on line.
From ~'69 to sometime in '72, the oval label had the Guild G-shield at the top, two lines of guarantee text, the model and SN, and Guild Guitars, INC, no factory location at all (this is the label my '72 D-35 has, but I don't have a pic).
From sometime in '72 to '75, Guild use a label with Guild in small script at the top, and made in USA as the last line of text, but no factory location:
According to Hans, the Westerly,R.I. first appeared on the label by ~1975. This label would have Guild in large script across the top, like this:
Westerly is in the arc of text along the bottom.
A different style of Guild script label with the Westerly location appeared sometime later (after '77, because it's not in Hans' book, but before my '94 DV-72s were made):
The possibilities I see are:
(1) The D-25 is actually from an earlier year, before Westerly was included on the label; or...
(2) The factory used an old label on a post-75 D-25 (Guild is notorious for using whatever they had on hand); or...
(3) The label has been replaced with an older style label.
The SN could confirm/exclude possibility #1. A pic of the label might help with #2 or #3... Hans is sometimes able to tell you the name of the factory worker who wrote in the model and SN.