Which headers you go with depends on what you want to do with your car.

I have observational experience with Spitfires, 2 friends are using them; one in a 65 Dart 273 4spd car, a drive it anywhere car, the owner loves them; the other is a 66 Barracuda, 318, auto, drag car that so far has gone 12.7's in the quarter, the owner likes them. I have a 65 Barracuda drag car, 360, auto, and a set of Doug's "D" Dart headers. They are not for the faint of heart, and you don't want to take them off and put them on alot, it gets old real fast, you do not need a special starter, nor do you need a mini starter, clearance is best with a standard starter. They do work well though.

I do not know anything about TTi's other than they are out there.

Cutting the cross member for exhaust pipe clearance is not too hard, but you do need a welder or axcess to one.

Good luck,

Jim Burch