Seriously?Yes, I do not like stainless, I believe I have made that clear. You can use whatever you like, it's up to you. You asked for advice, I gave you advice based on my experiences.
No, no he most definitely was not.--
You havent changed a bit Trent.. lol
News for you mate.. remember those JASMA headers for the GT4 that were stainless? They worked quite well.. and did not crack as you kept telling me they would. haha.
I took them out in the end as the heat generated was too much. But there was a noticeable increase in power. Only going by previous experiences, I would not waste my time or money on fitting them. Clearly they weren't worth the "noticable increase in power" seeing that you removed them.
Extra weight = Greater strain on braking system, there are reasons for signs like these. They should also state(however don't) caravans and car trailers as well. At least use a lower gear especially on hills.
Sorry to say but it sounds like it's game over. From what you described you have overheated the engine and possibly melted something. One last thing you could try whilst the plugs are out is to get a bar and socket onto the crank pulley and try and turn it over(clockwise direction only) by hand. If it doesn't move then I am sorry but you will need to replace/rebuild the engine.