On my '65 when installing the TTI exhaust, I did not agree with starting at the rear-that just won't work at all if you ask me. It was near impossible fitting in the passenger side head pipe, but I finally found a way to do it (and now I forget what my strategy was, unfortunately). Then to prevent the same header pipe from rubbing on the Torqueflite transmission (near the oil pan) I did have to shim the passenger side motor mount up a little bit with a small metal plate (I think it was only 1/8" or so-not any more than 1/4" for sure). Holes behind the rear seat do have to be drilled for the large muffler brackets. Then I had to find a longer rubber brake line hose (rear) to prevent the driver's side tail pipe from rubbing on it (but that might have been an interference problem only because a previous owner had swapped in an 8 3/4" differential).
and 90 degree oil filter adaptor
A few years later I tore the entire exhaust system loose when the clamp on the H-pipe got hung up on a huge speed bump (the clamp was installed with the ends of the "u" and the nuts pointing straight down, which limited clearance just enough to cause a problem. Photo #1 shows the passenger side motor mount shim I used. The other photos show the tight clearances with the passenger side torsion bar, Torqueflite oil pan, (probably before the shim was placed), the oil filter adaptor bolt, and the transmission crossmember clearance on the passenger side.
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