probably not. The 67-up cars are a wider chassis so you will most likely run into clearance issues with the steering and/or front frame rails.
If you can weld, its almost worth it to make your own headers, that way you will know how everything is going to clearance. otherwise you are looking at paying big bucks for a set of early-A headers. that is if you don't mind doing the work instead of spending the money.
I think that is the route i am going to have to go with my 64. it has a set of Hedman shorties on it now (which are SUPPOSED to fit early A's) but I had to use the Ford tool (big hammer) and also raise the motor up 3/8" to get clearance around the manual steering box. not pretty at all but its functional.
Good luck with it.
-Tim