La 318 mount don't fit 5.9 magnum.

Shainesboostin said
Hmm, I'll have to look for one. Another thing, your actual rubber mount, under the bracket...Looks different than mine. Mine is just a flat rubber mount that has a bolt threw the k frame.

He has the later "biscuit" mounts, the 72 and earlier cars take the "sandwich" mount that you are referring to.

Here's the 340/360 repro sandwich mounts:

Engine Conversion and Replacement Kit