Kickers are traditionally mounted on the port side of the centerline. This lets the boat steer a little straighter despite the off center location of the kicker. The reason has to do with the clockwise rotation of the propeller. If you only use the kicker for low speed trolling, the side that you use shouldn't matter much.
Sorry, but I can't recommend a particular mount other than to suggest the heaviest duty lift type mount that you can find.
Mounting Scotties on Gradies can be a challenge. If you have less than a little over 4" of clearance inside of your gunwales, you won't be able to use the top of the gunwale tilt mounts. Even if you have enough clearance for proper through bolting, you might not be able to tilt the downrigger (at least that is the case on my 226). But since the 192 doesn't have a bolster pad inside the cockpit, you could be OK. The L-shaped mounts should work in any case as long as you have around 4 1/2" of clearance to bolt them on the inside of the gunwales. You should use a 1/4" aluminum backing plate with either installation.