m44 thermostat replacement and spark plug question

[aziankingz]

hi, I am new to BMW and noticed that the m44 motor has a thermostat which comes with the whole assembly attached. When I change the thermostat, do i need to use any gaskets or silicone any areas when replacing? Also, is it just as easy as unbolting the old one, removing it and putting in the new one?

I ordered this thermostat with housing - hopefully it is good:
http://cgi.ebay.com/ws/eBayISAPI.dll...m=200383973460

Also, I am an NGK guy, but was wondering how autolites are since all the autostores around me seem to not have NGK in stock, and autolites are like 1.49 each.