Quote:

From the 70-71 Factory Parts Book. Jan 72 revision.

w/440 Eng. 70 - 3404802
w/440 Eng. 71 - 3466994 & 3466995




It would be nice if someone had an earlier version of the parts book which could confirm what the conclusion is, that earlier up to Jan 71 it was an H pipe with only one part number then to the two part numbers mentioned above.