Headers in a 66 fastback

I am having some issues regarding finding a set of headers to fit my car.
I am looking for a set of long tube jet hot coated headers that will fit:
1966 Mustang fastback with a FRPP 347 450hp "Z" alum. head crate engine.
The car has a cable clutch and a blowproof bellhousing.
Any suggestions/recommendations would be greatly appreciated.
Thanks,
Scott
 
Ran across Ford Performance Application."FPA".
They just developed an equal length long tube header that is ceramic coated inside and outside that fits my combination. I ordered them yesterday.
Thanks for the replies!
Scott
 
To late..
I have already ordered the long tubes. FPA has assured me that this design tucks up underneath the car very well.
In regards to "shorties". You may be right I may not notice the difference powerwise.
I do however love the look of long tubes as well as the sound that they make..
Scott