The '92 engine isn't exactly the same as the '94/'95. It is better because it has a forged bottom end, but the intake doesn't have an elbow, so you'll have to do a Throttle Body modification. Not a huge deal, since a lot of '94/'95 guys do it anyways.
You may need to find a '94/'95 GT in a junkyard for things like the K-member.
Are you planning on keeping your transmission? The 4r70w should bolt up right up to the 5.0, but you may run into other issues, like how to control the shift points.
It might be easier to convert to a T5 if the '92 has one. But you'll still need an adapter to make the fox body tranny work on an SN. But this way you should still be able to use the Fox's ECU.
Look for articles online about '94/'95 V6 to 5.0 swaps. I know MM&FF did one.
Then look for articles about the differences in Fox and SN 5.0's. There have been threads about this in the 5.0 forum, I believe.