I leave my Slow N Sear in the kettle 90% of the time. For the burner tube, I copied the idea that @ed3120 and @pbe gummi bear have pioneered - positioning the ignitor to the right of the mounting bracket. This allows you to focus the flame right under the fuel when using the SNS.Winz
The burner tube is the same for all gas-assist Performers. The regulator for the SSP is different than the Gen2 and all later Performers (which are all interchangeable, I believe.)