just that one clamp is fine.
If you don't want to use a ziptie, order this to keep the rear section from moving.
https://www.amazon.com/Double-Split...ents=p_bore_diameter_derived-vebin:0.5+inches
Bumping a dead thread. Picked up one off Ebay from speedyracer for $199 shipped. Going to be mating up to an APR downpipe. Hopefully not too loud. But for half the price of a dual canister setup, worth trying!