GGJaguar, I'm guessing from the headstock logo design and the two knob controls that load from the back, that this is one from late in the run? Like from maybe #1500 or higher?
It's interesting that Guild would change design during a small run. Like on the S-25/S-250/S-275 runs, you'll see the knobs and switches in different positions between guitars of the same model number. For example, look at these two S-25 models and how the knobs and switches are in different places and even the shape of the lower bouts and the "horns" of the upper bouts are slightly different.
Yes, GG's is a late-run X79. Guild has a fair few solid body models with many variations. The S60D has at least two knob layouts, for example. The S300s have different designs toward the end of the run where they stopped having pick guards.
Back to the pickups, I don't think that the black-covered Dimarzios are XR7s. Hans would probably know but I imagine that's a next-book topic. Black-topped Dimarzios were sometimes found on Nightbirds, too, and I don't think Nightbirds ever came with XR7s.
Dimarzio was terrible about identifying pickups when they made them. I've emailed their tech support a few times trying to identify old pickups with nothing but "Dimarzio - Made in the USA" on the back and most of the times the best they could give me was, "Well it could be this or that" but rarely a definitive answer.
