Getting ready to put a 426 Hemi in my 69 GTS Dart. Will be useing a motor plate and headmen headers, the car is a 4 speed. I know it will it take some thinking to get it done right.What I need the most information on the manual gear box and master cylinder. Running stock 2x4 manifold I want to keep it under the stock hood. Thanks for any help.

I did a 68 Barracuda and I don't think you will be able to use off the shelf headers. Mine were custom made by Mike Roth of MR2 Performance (Lebanon, Indiana) as they have to be "snaked around" the gear box, torsion bars, starter, etc. I'd be surprised if any manufacturer had a set that will work. You can use the manual gear box but it will get hot (no big deal)as the header tube will be extremely close to it.

Mike also has the offset plate for your master cylinder which requires a modification to your brake pedal assembly. Mike can do that too.

Some minor modification to your right side shock tower will be required.

I'd be surprised if you can get everything under a stock hood without a scoop unless you are using a very low profile intake and then I would question the clearance between the carbs and hood. There is someone selling a Hemi Dart in the A body section. You might contact him and see what he ran into. My Barracuda is the second ad. Wish you all the best as these Hemi A bodies are a "RUSH" to drive.

If you're planning to use the stock steering column you may need to notch a portion of it where it comes in contact with the back of the head. I'm using the ICH Legend 1 alum. heads but your application might be a little different. Just a heads up, so to speak.

As I recall, the Hemi A cars had spacers between the frame rails & K member to effectively drop the motor for clearance. They had taller intakes, though. Last I heard Hedman still makes a header for that application, but I would not expect this to be a "drop-in" deal.

I have worked on a couple of these swaps, but both cars were using a custom k-member, coiled over/r&p steering. TTI has a set that bolted right in and have very good ground clearance for use w/coiled front. I can get you hooked with the guy that built the k-member, the Duster has been running this setup for ten years now. Here's a link to the last swap in a Demon:
http://www.forabodiesonly.com/mopar/showthread.php?t=88358

68 Dart with 1/2 inch spacers and K frame. Hedmans for Hemi A Body hit t-bars, steering linkage, starter, and if pass inner fender is not clearanced they will hit there too. I had the Hedmans modified to clear above areas, ended up 20% Hedman, 80% custom (see attached). If I had to do it over I would just get custom headers built and skip the aggravation. Also you need to cut 2 inches off bottom of steering column tube for better clearance.

I ran into the same issues with my Hedmans. Go figure. But they discontinued the Hemi A body hedders this year, so no more problems there.

If those heads are taller than stock heads, it will cause you extra problems. My buddy used Indys on his project and they hit big time. You might check on the valve covers too. I think that the new ones from them are notched in the critical area.

Anyway, make sure that the parts that you choose for this project are dimentionally the same as stock pieces or you are in for additional work. Guess how I know.

I had problems with the Hedmans and then the external oiling system, I got so frustrated I wound up installing the engine in my 72 road runner.