I just took off a pair of HP 1968-1970 340 exhaust manifolds. I'd like to trade them for a set of TTI headers for my 69 Dart SB. The casting numbers are 2863549 date 1-20-69 and 2863553 date1-2-69? (hard to read). I'll also include the two special bolts on the right side manifold. The heat riser was eliminated at some time in there life. i guess if you really wanted to you could add it back on. They sealed real tight and had no leaks