Most of us 67-up A-body guys, run headers, but on the proper K-members; and interference is minimal. I cannot say about adapter mounts, which I have never used, nor ever will.
>I have a 68 Barracuda, in the which, the underhood is identical to yours. On the 1970 Duster K that is in it, my 367 accepted TTI headers with just minor fudging. I too have power steering/power brakes/and the short oil filter straight to the block, with no adapter. AND with an A833 4-speed, so all that clutch pedal junk is in there.
But, I did have to block up the car and slide the T-bars back, which was no big deal.
Another time, I put the headers in before the engine came down, and the T-bars in-situ.
Another time, I put the engine on the K with the headers attached, and shoved it in from the bottom. This took more time, but at least it didn't scratch the paint. That engine was swapped in/out 5 or maybe 6 times before my son "commandeered" it, lol.
>For a retro-fit with the engine already in there, I had to free the engine, hang it on a sky-hook and move it over to the passenger side a wee-bit, then slide the drivers side in and hang it floppy-like; then slide the engine back and and install the passenger side; then drop and secure the engine. And then finally, install the gaskets and bolts.
>If you have cheap-er headers that have one tube going under the steering and no slip-fit #7 tube, then you will have to drop the centerlink, which takes about 5 minutes, no big deal. With this type of header, the slanty T-bars and shocks should be ditched, as if you don't, this may lead very quickly to a smooshed #7 tube. I highly recommend the thickest T-bars you can get including up to the 1.03s. If you have 383/340 bars, (.892 IIRC) you can use those with HD shocks.
>do not be afraid to use a header with a slipfit tube. The slip will soot up right quickly and then it is sealed. The only way to get it apart is to soak it in penetrant.
> do not think a stock 318 will not benefit from headers and dual exhaust. Back-pressure will kill both power and economy. Your goal is to reduce it as close to Zero as is possible without breaking the bank to get it done.
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I once ran a stock long-block 8/1 smoggerteen 4bbl, with nothing more than TTI headers and a 3" full-length dual exhaust, which was WAY overkill; but she was a pretty good ripper, and was real easy on gas. I married that engine, to an A904, a wide-ratio A998, a 4-speed, and an A833overdrive, and finally with a Commando 4-speed with a GVod behind it; and with various gears from 2.76s to 4.30s, always with a SureGrip. When it had an automatic, it also had a 2800 stall TC. I loved that thing; and,I really loved that winter-motor. And so did my son who finally made me an offer that I couldn't refuse.
If you have never run a 2800, it takes a bit of getting used to, but after that you will find you can do fun-things with it. I would never go back to a stock TC. Mine is a Trac-Action from circa 1980.
Note to self; a 4-speed in winter, in snow, and no studded winter tires..... is a bad idea. That only took one trip to town, to remedy; and the reverse lock-out shifter got swapped out real quick.
