thank you for the info. that means a 5.0/5.8 swap would need motor mounts, front dress, headers, bigger rad and a V8 passenger side wiring harness and ecu. would the drivers side wiring harness be the same for the V6/V8 or would I have to change that as well?
Oh, I can definitely hep you out - I swapped a 95 Cobra drivetrain into my 94 V6 chassis. The driver's wiring harness leading to the fuse box will work, but if you have ABS you'll need to make sure you get a 5.0 harness with ABS. My 94 V6 did not have ABS, so mine just plugged in.
The radiator was the same between the 3.8 and 5.0, though a bigger radiator can't hurt. You'd be better off finding a donor car for all the extra brackets and parts you won't be able to find anywhere. I bought a wrecked Cobra off of eBay that had frame damage, so I had everything I needed.
You can make do with the V6 axle for a while, but it's not really strong enough long-term for the torque from a 5.0. If you do switch the axle, you'll need to swap the hard brake line that runs from behind the front passenger wheel all the way back to the axle.
Oh, the transmission crossmember is the same between the 3.8 and 5.0 cars. The 5.0 transmisison has a bracket that moves the tranny mount back far enough to match up with the crossmember.