I used the downey motor mount with a 327. There was a problem with trying to mount a powersteering pump. The 327's use the same bolt holes for the powersteering as the downey does to mount the channel to the block. With a 350 this should not be a problem since the pump mounts to the head. The downey mount does not center your engine. It is slightly offset to the left (driver side), just like the toyota 6. You need to use a rear dump manifold because of clearances with the steering box. Over the frame headers will not work, #5 exhaust passes directly over the return outlet. only 1/2 inch clearance. Cannot get the fitting and tube in. Any other questions about the motor mount system, let me know.
I can't give you a good idea on a price for the cradle, I installed mine over 20 yrs ago. I now have weldin's to accomadate the powersteering pump. If I were to do it again, I would use the over the frame mounts that use the stock chevrolet motor mounts. I don't remember exactly where to locate these, but you might try Bob Firestone on the LCML list, or see if Woody has a listing on the tech section. As far as the rams horn on the driver side, the adjusting nut on the box hit the collector, just above the bolt flange. This was with the engine slide over toward the passanger side as far as it would go. I have been considering block huggers myself, but I would like to see a pair on a block and take some measurements
the cradle mounts are ok, but weld ins are the way to go. A victim of a front end accident (cruiser was ok) had the engine break free and go through the radiator about 4 years ago in Tucson. The plate failed so I hear. Needless, he switched to weld in mounts after this when repairing the truck.