I do mine warm too. Just be careful. releive the pressure by taking the cap off like Danthurs said and you'll be fine

You don't have to take the hose off. Just pinch the upper hose and take the two 10mm bolts off the tstat housing, it will lift right off the block with a little wiggle about a cup of coolant will come out in the process

ok I got the hose off and the old thermostat out had to use pliers to get it loose, it does look pretty jacked up...so now I am going to put the new one in....man I feel like an old pro now

That'* awesome to hear. Most of nervousness is the fear of the car. Just be sure to check your coolant level after you get it up to temp once.

Make sure it'* all clean. I will pour coolant in the hole until it'* full, then slowly put the new thermostat in the hole. this prevents and air from being trapped under the thermostat. then when it'* all closed up, pour coolant in the radiator until it'* full.

ok got the new t-stat in and flush with the metal...and tightened the bolts hand tight now I am socketing them to tightness alternating both of them....taking a little break...for a computer geek this sure exherts myself...lol

Wait till you try changing your exhaust manifolds.

ok the engine is started I topped off the coolant..and got all the bubbles out...now reving the engine a bit...and waiting for about 15 min to see if the temp gauge goes to 200F...then I will restart the car and see if the light is gone...crosses fingers..

OMG It worked!!! The Service Engine Soon light has gone off...I have completed my first repair of my bonneville....thanks to all you that helped this forum is a great resource for the technically challenged like me....thank you god...I am an SSE member now

congrats on the first repair!!! we'll turn ya into a grease monkey yet hahaha