hi paul ive learned alot from you already from reading archives. but on one topic i was confused. you told a guy his c8ve heads had non adjustable shaft style rockers. i have a set of these heads on my unfinished 460 project and these could have no way had shaftsyle rockers or pedistal type either. i bought these heads from a guy who put them on a 30 over 460 with flat top pistons. and it had to much compression. these heads have new valves, and hard wear i traded a set of nice d3ve heads for these c8ve heads and have since installed new studs and guide plates and have bolted thm to a 1979 era 460 rebuilt using stock crank,rods, pistons. the stock 460 pushrods measured 8500. i bought a set of length checking pushrods and using a 1.7-1 crower roller rocker i came up with 8550 to be the right length for the puhrods and when i checked for availability it turned out to be exact length for 429 cobrajet and super cobrajet. these heads were thought to be from a 68 thunderbird(thunderjet) but with canted valves,adjustable valvetrain, and huge ports could they be early cobrajet heads? am i on the right track on the pushrods? any help would be appreciated thanks