Re: v6 turbo
Yah if it's the turbo coupe then it's a 4 cylinder that made 145 and 155hp (1985). I'd definitely let that one slide.
You could look into a M90 supercoupe swap, but I'd only consider it if you have a pre 99.
The biggest issue for me with the thunderbird supercoupe is that the 3.8 in those cars are single port engines...the 99-04 3.8's are split ports. You are basically going backwards in order to get a half a step forward. If you have a pre 99 3.8 the swap is still a fair amount of work but your gains will be much better. I'd almost look for the entire engine at that point. They came with a forged crank and upgraded heads/pistons. Even so, you'll need the complete engine, wiring and ecu.
12 Black GT500 SVT PP l 2.6 Pulley/Idler l Airaid l o/r X l 305 NT555R's l Recaros l
04 Azure Blue Mach 1 / 03 Sonic Blue 3.8 / 14 Sterling Grey F150 FX4 402A 5.0 / 11 GT500 R.I.P.