Exhaust manifold bolts with or without studs?

[LuxBronco]

Hi,
In restoring my '74 302 back to original I ripped out the custom headers and got second hand one from TBP.
Since I needed to get new bolts I ordered bolts with four long bolts with studs in order to put the spark plug heat shield to it.
but four of the bolts are too short since the manifold is thicker on the middle cylinders than on the outer ones. Bolts are 2" but need to be at least 2 1/2".

but this got me thinking:
1. Do I have the wrong manifold for the 74? (Maybe older)
2. Are there supposed to be heat shields on the 74 at all?

where do I get bolts from that are long enauch?

 

[Steve83]

Pics & casting numbers might help ID what manifold you have.
http://www.supermotors.net/forums/thid-5972-how-do-i-post-pictures-sounds-and-or-videos

I don't think engines that old originally got plug wire heat shields; I think those appeared around '85~87 on V8s.

 

[Rustytruck]

My 1974 California Bronco 302 has spark plug shields, and the cover for the heat riser for the air filter housing. The exhaust manifold I believe its an earlier 1973 casting and it has a reinforcement rib running the length of the exhaust manifold. I had to replace it once since it cracked between the 2 & 4 exhaust port. The exhaust bolts are 2 different lengths and the studs I believe are 2 different lengths too.

California Broncos in 74 probably got the heat shields because the change to resistor plugs with the electronic ignition. In 1974 49 state trucks still had points and in 75 they all got electronic ignition. in 75 Ford was using the smaller peanut plugs and they are easier to deal with the heat shields. My 1974 with the heat shields is a pain in the arse with the bigger plugs.