I've got tamiya's m113a2 on the go at the mo and was disapointed to see that they never
put detail onto the inside of the vinal tracks,Now I have a spare set of vinal tracks from my academy IDF fitter kit would these be ok to use instead?

Compare the rubber track pads of the two. I believe that Tamiya made the newer type of tracks for the M113 and the Academy kit has the older type of track. I might be mistaken. Besides, when you glue the track down to the road wheels and place the side skirt, you can hardly see any of that detail any ways.

I think you mistook M113 tracks with Bradley tracks. New Tamiya Bradley includes tracks with newer style rubber pads, while older Tamiya and Academy kits have old style tracks.
US M113 tracks have never changed - they are the same since the begining of the service of the vehicle. Some countries use Diehl tracks on their M113's, but it is another story.
And Academy M113 tracks should be OK for Tamiya kit.

Best Regards,
Pawel