340/360 J head rocker adjust stud

1970 T/A challengers and AAR cudas with 340 six pack engines had 915 " j"casting heads with offset intake pushrod holes,and used adjustable rockers, (offset intakes). However , all other "j" heads had non-adjustable rockers.

i thought the 340 6 paks used the "X' head with adj rockers

82 cruiser:

I've had 3 sets of "J" head:violent1:s and none of them had adj rockers unless I put them on