Greetings - personally, I would not use Permatex as this product will, or can, tend to move into spaces you may not want it to go. While it's a great sealant, it will certainly give you some headaches if you ever need to disassemble the burner in the future. Below is a link to the product I was referring to. This particular sheet is 12" X 12". Basically, you cut the shape you need assuming the shape is something tangible and not threads on a nozzle. If you need a high temperature thread sealant, let me know and I can recommend that as well.
I have traced many components and cut the sheet with a scissors. If you can't trace the component, smear a heavy layer of cooking oil on the surface component and press it onto the sheet. When you lift the component, the oil will be your pattern.
This company has many sheet sizes to choose from. It's silicone so temperature is NOT an issue and it will last forever.
https://www.mcmaster.com/#standard-silicone-rubber-sheet-gaskets/=Good luck and I hope this information helps.