My Invader is back together and running again. As it turns out it did have a little meltdown that I couldn't see until I pulled the cylinders, which I believe was caused by dirty carbs. The previous owner had told me he had cleaned them last year, but I shouldn't have listened, they were pretty messy. Complete rebuild, cylinder and piston off a spare engine with new SPI rings both sides, Wiseco Gaskets and seals.
I threw one of my New Breed ski conversions on it too, unfortunately the blue does not match very closely.