The springs on my 65 are relocated into the frame rails. Narrowed diff and mini tubs too. Stock gas tank.
I used the 3" x-pipe kit from TTI with offset inlet and centre outlet mufflers. The TTI footnote 57 indicates that exhaust will not fit with relocated springs. Basically, that means it will not bolt in directly but you can make it will fit.
The instructions says to start installing at the back and move forward, but because of the springs I started at the front and moved back. I had to shorten the x-pipe section by about 4"; not certain why but had to for proper fitment.
Once the x-pipe and mufflers are firmly in place, start fitting the tail pipes. Spacing over the diff and between the shocks (narrowed diff) is tight so adjust the pipes for clearance. The flange on each side of the gas tank will interfere in some spots, so bend the flange up for clearance. Springs and rear hangers will interfere also. I spaced the rear tailpipe mount using a long bolt and adding washers until there was no contact through the full motion of the rear suspension.
Lots of trial and error, in and out, until everything fit. It is snug, but I have no contact or rattles.
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