By coincidence I have a Glenfield 25 and a Marlin 25N, so I took them out to compare. The Glenfield 25 is from 1978 and uses the old style of magazine with the release lever built into it. The magazine clips onto a metal piece up inside the mag well. The Marlin 25N is from 1995 and uses the newer style magazine. That gun has the mag release built into the base of the mag well as part of the rifle. The bolts seem a little different as well. I checked Numrich's and the parts numbers are different for the bolts so I think they are not interchangeable.
I would guess that many parts are similar, and some may be interchangeable, but not all. I know the older style mags are available because I just bought a couple, but they are getting pricey. I paid almost $45 for two shipped from Dick Williams.
Check Numrich's or Brownells for specific parts.
Vet47, thank you for sharing that information. i could tell both were bolt actions but really couldn't tell any other differences from the schematics. i have to agree, that if the part numbers are different, they probably won't interchange.
i am sure Dave will find this helpful, and again thank you for looking at yours and helping out. very much appreciated by all.
In addition to the changes you have noted, I believe the safety was also changed. It seems that everywhere I look, the safety is always noted as to old or new. I have a 1970 model 25 but do not have a 25N to compare.