Generally speaking, if the kit is a German subject and was issued by Dragon in the old "Imperial Series" (numbered in the 9000's), then it's very likely to be based on a Gunze original tooling.
These kits include:
PzIII family (including Stug.III's)
PzIV family (inc Stug.IV's)
Panther family (Inc Jadgpanther)
The Gunze kits were little gems in their time, coming with styrene, PE and cast metal parts, and often MK tracks. When Dragon bought the moulds, the cast metal and PE was replaced with styrene parts and the MK tracks replaced with (then) newly tooled styrene indies.
Dragon also did a similar thing with their 1/48 aircraft range, the FW-190 family, Me-262 and He-162 kits and others which escape me, coming from TriMaster moulds.