You can have a linkage (rod) setup or a cable throttle. They are easy to install. The stock one has a "bell crank" as shown. You do not need a kick down for a 350/350. If you want it, you may have to set it up/adjust it again to operate with the "new" linkage. As Bill says, you would be using the bracket you have now and kick down cable stays attached same as now.

P.S. Your heading does not match your question? I see your other post is asking that question. I have installed a Lokar Nostalgic shifter in a 56 with a 350. It looks like the original 4 sp and attaches to the transmission and comes up thru the floor. I don't know the difference between "Lokar floor OR transmission mount". It's the same thing. Anyway I thought it was neat looking and functioned well after tweaks.

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn