How to best clean an old (tossed aside) tank

[xiamin]

My 55g tank has been in storage for more than a year, basically in the (dirtfloor) crawlspace under the house. I kinda neglected it b/c the last fish in there died of a mysterious ailment 6 months after set up, and I didn't want to sicken any new fish. I meant to throw it away but now it seems it could be put to good use. What is the best way to clean it thoroughly? Bleach? Vinegar? Dish soap? OR is it better just to start from scratch? Previous tanks were smaller and disease free so I just cleaned them with one of the above. I'm not sure if the size makes a difference in how to clean in preparation for new set up.

[Pufferpunk]

http://www.skepticalaquarist.com/docs/s ... over.shtml

[xiamin]

Thanks!