273 to 340 swap in 64 cuda auto advise needed

In dead from shoveling snow for 7 hours, so if I'm scatter-brained im sorry. I keep hearing there.are early model 340 driverside manifolds that will fit on my 64 cuda with power steering. I have a picture of one installed but no definite year or p/n.yet I hate to be buying 340 manifolds willy nilly. I'm afraid I'd end up with a collection. I am convinced someone here knows
It may just take a while. I can't be the 1st one to do this
I didn't know the 273 intake will bolt up. It's good to know. It will simplify linkages if I go that way.
I do have to say though there are a lot of great people here on this site