Torque arm should fit with little to no issues...the dimensions of each mounting surface on the 12-bolt and 10-bolt are nearly identical. Bolts will transfer right over with the arm...
The only other thing you'll need to go along with that 1350 conversion u-joint will be a torch to get the stock u-joint out...it is held in with injected nylon that has to be melted to get the old joint out.
I can't think of anything else other than that...do you know if it has sway bar mounts included? My Strange came with them already welded in place...if you don't have them, the stock muffler-clamp style way of mounting the sway bar can be used with a little tweaking in the form of grinding (if you don't rotate the bar a little, it'll hit on the rear cover). If you don't want to do that, you could always do the Spohn bolt-in sway bar mounts that put the sway bar a little lower on the rear...that will also keep it from contacting the cover.
__________________ 2008 Viper