A518 Kickdown Cable & Mount Help??

I'm with Redfish.
I worked in an autobody frameshop for awhile,and this makes me nervous!!
The loads from the torsion bars, plus the weight of that very heavy OD trans, plus the added weight of the fabbed up mount itself are all pushing down on the center.
I will concede that if there is no rust anywhere on the remaining crossmember and the car is not hammered on it "might" hold up.
But some crossmember rust, a few rough roads, and a little time, I can guarantee that tranny will be digging up asphalt.
To go the route you have with no "up and over", I'd like to see a reinforcement plate incorporated(welded) to the crossmember that is also welded firmly to the torsion bar tubes. The mount should have the bolts further apart(too much load in one area). Do that on front and rear, and then do the other side the same.
Go to a post by Old Geezzer, "5.9 magnum in a 73 duster" for some crossmember reinforcement photos.
http://www.forabodiesonly.com/mopar/showthread.php?t=41302
On the Linkage? I think a spacer and longer bolt will be fine.
Good luck.