how to remove thermostat from 04 Beetle 1.8?

[duanek]

my 04 new beetle is throwing a P2181 code, I already replaced the temp sensor. I bought the VAGCOM tool with software, and can see that my engine temp never goes above 75C. So it looks like thermostat is stuck open. I drained the fluid and am able to get the thermostat hose off, but can't figure out how to get a wrench on the lower thermostat housing bolt. Is there a special tool or something? Should I remove the alternator first? I put it all back together and am currently driving it daily, but would like to get it fixed.

thanks for any help you can provide, Duane