I have a '95 T-Bird Swapping in '99 newer 4.6

I cant help with the swap, but since your gonna have the other engine out... why not add some cams, or port and polish the heads? Bolt ons will help a little, but id do the big stuff while the engine is out.

The newer 4.6L are not a direct bolt in. You will need a bunch of 96 - 97 4.6L parts from either a mustang or a TBird, and you will need the 96 - 97 TBird upper plenum or accomodate the extra vacuum fitting required for the brakes on the TBird. I suggest you go to http://www.tccoa.com and do a search over there. Lots of people have done this swap, many prefer the Explorer 4.6L 2V swap as it uses an aluminum block while the 99 mustang is iron.