Hey all, this will be myvery first post here, so appoligies for any faults. so i set out to change the thermostat on my gs300, the old one was stuck open. (image of the manual on how to do this) steps (in short), drain coolant remove lower radiator hose remove thermostat housing swap old thermostat for new one reinstall just because i was bored i decided to test if the new thermostat opens before i set of putting it in. get a pan fill it with water and make it boil, luckily i have an IR thermometer and it read about 82 degrees (celcius) when the thermostat opened up. (in the image it's still closed fyi) so after the engine had cooled i just pulled out the lower radiator hose, nothing special here just make sure to have a big bucket in one hand while doing this, also this is not necessary but i replaced the factory clamps on the hose with these ones, after that you find the thermostat housing with its 2 10mm bolts holding it in place, undo both of them (carefull not to loose them, they are pretty small and will fall immediately) and after removing it, its all really dirty as well so i cleaned it off with some brake cleaner. this is what i looks like when cleaned together with the new thermostat. for reference here is the page on thermostat removal form the workshop manual (sorry i dont know how to rotate it) as you can see the thermostat already comes with a rubber gasket so dont worry about that. torque specs are 8.8nm which would mean just handtighten it the thermostat has a little jiggle valve on it make sure this is on the highest part (so pointing upwards) this is so that air can go out, also the thermostat housing has this little spot indicating where the jiggle valve should be. note the spring side of the thermostat has to be on the engine side (very logical but it doesnt hurt to mention) and thats it you have removed and now swapped the thermostat, all left to do is put it all back together. put the thermostat in the housing and slide the housing in its spot, tighten the bolts and that re mount the radiator hose, get your rag and clena off all the spilled coolant. fill your system back up with coolant (fill the radiator, not the reservoir) squeeze the hoses to purge air and start the engine after you are done, dont forget to top up the reservoir after you filled the radiator and keep an eye on the system for the next few days. top tip; if you installed those clamps i mentionned, you'll have to get back in there and retighten them as the rubber will compacten under the tension of the clamp and this is what it looks like all finished hope this may hlp someone some day, please leave a comment on wheter you liked my first post and ill keep posting things i do on my car, next job is probably going to be a valve cover gasket.