That makes sense . Run what you got I guess. The t bird might not look as pretty when it is all said and done .There is most likely a LOT of them around.
I have owned a herd of t birds in the late 90s and a few cougars. Never had trouble with the rears. The supercoupe I had had the 8.8 and the axles were the larger size compared to the v-6. IIRC the v 6 could have the 7.5 or the 8.8 but both had the skinny axle. the supercoupe and te v8 cars had the 8.8 and the thicker axles. Just thought it was worth the mention.
My oldest brother is looking for a miata to put a 4.6 liter in and from what he is telling me they guys are also putting 8.8 rears under them. must be they arent to hard to squeeze in there.