Glad to help. These older bikes are great to learn wrenching on.
If you don't want the hassle of buying tools right away, take the rear wheel to a bike shop and have them swap the freewheel for you. Otherwise you'll need a Shimano-splined freewheel tool and a chain whip. A decent chain tool is a good investment regardless (I use a Park model). Nashbar has some general purpose tool kits for reasonable cost, especially on sale. I bought most of my tools the expensive way - one at a time!
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2010 AB T1X ** 2010 Cannondale SIX-5 ** 1993 Cannondale RS900 ** 1988 Bottecchia Team Record ** 1989 Bianchi Brava ** 1988 Nishiki Olympic ** 1987 Centurion Ironman Expert(2) ** 1985 DeRosa Professional SLX ** 1982 Colnago Super ** 1982 Basso Gap ** 198? Ciocc Competition SL ** 19?? Roberts Audax ** 198? Brian Rourke ** 1982 Mercian Olympic ** 1970 Raleigh Professional MK I ** 1952 Raleigh Sports