Does anybody have an idea what kind of headers on a V8 flathead would fit with a jag ifs set-up on a '53 F100? I'm looking to use center dump headers on mine (from Red's headers).
By the way, the jag crossmember is a little to narrow for the '53 F100 frame. Is it best to cut a small piece out of the crossmember, or to narrow the frame a little bit?
Berre

 

I can't help on the flathead headers with the Jag IFS other than to say that center dump short headers are the choice on the Jag/SBC setup which is what I am in process with. My suggestion is to fitup the Jag IFS first, mock up your steering setup and then check out headers for fitup. I do not know if someone out there has setup the Jag IFS with a flathead.

My truck is a 49 which has the rails pinched 2 inches narrower in the front than your 53, i.e. nominally 32 vs. 34 inches wide. The Jag installation in the 34 inch wide frame has been done by others both ways, either notching the frame to clear the rear of the upper A arm or notching the Jag xmember to get the upper A arm rear pivot point above the frame rail. I believe that those that have done it in the latter manner have installed the upper A arm after installation of the Jag crossmember. I am not at my home comp[uter today but will post a great website to help you. It is on my favorites at home and I can not remember the address. Check out the gallery for 55 F-100 Paul on this forum.

EDIT
the website to check out is www.uk-hotrods.co.uk/garage_scene_stuff/me/page%20l.hth
EDIT#2 I just tried the above website and I had to go to the uk/garage scene and click on "Holmsey 1955 F-100". It is a GREAT website!