There's a handy chart "someplace else" so no need to duplicate it here, check this page:
http://www.bigblockdart.com/techpages/techindex.shtml
http://www.bigblockdart.com/techpages/moognumbers.shtml
HOWEVER before you put lots of money, work and time into that front end, ask yourself some questions:
"Will I be happy?" with the stock suspension?
"Will I be happy?" with the brakes I have now?
Otherwise you will be RE-doing some of what you are about to entail
First, the idler arm on a 67 is one year only, and expensive. This CAN be remedied, by doing some fabrication, so that it will take a 68 / later idler arm
Next, the old style pillow type engine mounts were replaced in 73 with better "spool" mounts, and the later cross member will bolt in, solving both the above problems. The mounts, however, are not exactly a "must."
The next thing is wheel bolt pattern...........
and brakes
If you think you might put more power in the car, you might want a later / bigger rear axle, and that means the larger wheel bolt pattern after 72
And.....if you want to improve the brakes, THAT might mean the larger bolt pattern if you go with 73/ later a body brakes. If you go with the later brakes, this means changing the upper A arms, spindles, and lower ball joints. So that much would be re-done
You CAN upgrade the small bolt pattern brakes and stay with that bolt pattern, but this somewhat limits wheel choices.
Just some things to make you go "hmmmm"
