Although the general principal of the Goggles remains the same (A PVS-5 frame, side knobs and one lense being longer than the other, there are still clear differences that spell the two Ecto Goggle props made for the two films apart):
Ghostbusters Green/olive drab frame.
Black side knobs (flat outer face).
Short battery cover.
Genuine NVG power switch (missing in most scenes).
Long black/silver lense (camera lense)*
Short fully black lense (might be from a telescope)*
Black snaps.
Labels on both lenses and on left-hand side of frame.
Four black hex bolts on front panel of the Goggles.
* Lenses are largely smooth on the side, excluding thumb screw pieces and block at the end of the silver lense.
Ghostbusters II Green/olive drap frame.
Black side knobs (inner detail on outward-facing side).
Tall battery cover (looks like it could be the standard short battery cover with a stunt Proton Gun knob added).
Genuine (or copy).
Dark grey/silver lenses (appear to be mostly scratch built, and appear to feature model tank tread parts), riveted to frame.
Green snaps (painted over)
The only label that appears to be on these Goggles is the side label, but looks to be painted over)
No hex bolts on front.
Tank model parts on front of Goggles between the lenses.
Additional fitting on the top of the Goggles.