pushrod length

I am replacing the head on my '74 258 with a recently rebuildt head,intake and exhaust from an '87 Wrangler. I have a bad lifter and a bent push rod right now so I figured if I pull the head I would be better off using the '87 head intake and exhaust too.
The push rods, according to the parts store, are 9.72" for the '87 and 9.565 for the '74, lifters are the same part number.
I don't know which length push rods to get and thought maybe someone here may have an idea. I have the headset for the '87 for the intake and exhaust gaskets. The head bolts are the same size as the '74 and will be new too.

 

The rocker geometry determines the pushrod length, and those come along with the head, not the block. Use '87 pushrods with an '87 head.

The '74 manifolds should be compatible with the '87 head - certainly the '87 manifolds will fit on the '74 head.

If it were mine, I would not bother to swap heads. All the 258 heads are the same performance-wise. For some reason, for a year or so around 1974 Jeep switched from the stamped rockers to the cast rockers in the 258, then back. I don't think there's any reason to want stamped over cast, or vice-versa. Unless the '87 head is clearly in better shape than the '74 head, you're just bastardizing the motor for no good reason - I would not change it for change's sake. JMO.

 

Thanks for the info timgr. I live in the desert and this is my DD so it's prudent to keep parts like an spare head around for emergencies. The old head will be rebuilt and put aside for that reason. The head going on has a little over 8K miles after service and the P.O. dropped a screw down the intake and busted a piston. The head checked out fine at a machine shop and the late model intake is a 2V looking at a carb upgrade and hopefully will help help with warming up this cold running engine in the winter.