So that's a likely cause for the detonation problem. Gears went in easily, the fancy external filter sump and lightened flywheel, etc were all assembled into the bike. The trans seal was replaced easily. Next mod was the throttle itself. The Ducati switch requires a little rewiring to mate with the Guzzi harness and the master cylinder needs to move up the right hand bar by 8mm to fit the new switch and throttle.
Cables route easily, the inner RH fairing panel is discarded to allow space for the cable runs.
Looks factory and fits beautifully. I reset the ignition timing and balanced the carbs with vacuum sticks. On my test ride today, there was still trailing throttle backfires and a little bit of spitting. Idle to off idle transition seems smoother too. It starts easier, warms and idles almost instantly, and is smoother all the way around with a big, fat midrange now.