Whatever you do, pay attention that it does not affect the fore/aft position of the engine and mount relationship to the k-frame mount, or you may have problems dropping it in...
Since all that is installed is a bare K frame, i have room. I plan on bolting in the pass side mount, bellhousing, transmission etc to make sure its all lined up, using a 2x4 block and a floor jack i will get the engine sitting level. Then i will mod the LH mount to fit while the rest is sitting correctly.
Looks to be that the aft engine ear on the LH side is moved fwd about 1/4" on the 340, 360 compared to the 318. The FWD ear on the LH side is in the same location as the 318, and the pass side is the same as the 318. So its actually the addition of a spacer between the LH rear block mount ear, and the engine mount bracket thats needed.
I have a pic i downloaded, however i cant get it to load to show what i am talking about.