I am running a DA100 with KS Canisters and want to add smoke oil injectors. I am running a Sullivan Skywriter smoke pump that is using a programmed mix with my throttle channel. Where should the injectors be located?

1) Header pipes close to the exhuast port, say 1" from the engine?
2) Header pipes about 4-5 inches from the exhaust port?
3) In the Canister muffler itself?
4) How much of the injector should be inside the header pipe?

thanks in advance.