I had the same problem a few years ago when I sprung a low pressure leak in my radiator. i went to the local autozone, o'reilly's and everywhere else and they had plenty of different radiators that LOOKED very similar, but none that have the tranny cooler lines. Anyways, just wanted to let you know I have noticed the same thing....I saw the REAL GN radiators somewhere (maybe poston buick???) or Kirban Performance but they are PRETTY expensive. If I were you and if you have ANY work done on your tranny I would reroute the trans cooler lines and hook them up to a external tranny cooler. Since I have done this to mine, the trans runs MUCH cooler and so does the engine. Of course there is the reproduction radiators for about 250.00 I believe...Hope that helps alittle. ; )
-Rich