My opinion and mine alone - a '65 Impala, unless it's a convertible is not high on many folks list of favorite cars. At a show, even a very nice one will barely get a nod. Out driving - it's OK. A 'bucket properly built and dressed out will always be an eye catcher and conversation starter. If it has a top, you can always add side curtains and even a heater - when I had mine, it was driven as often as possible and even got snow on it several times when the temps got into the 20's. Rain? If you don't have front fenders, the tires will sling slop on you in a turn. Fit you? I'm 6'4"/200+ and had absolutely no problem with mine. Yeah a bit short on leg room, but really no worse then my current car, a '31 Ford roadster and actually a bit easier to get into.

What you need to do is determine what it will end up costing you to bring the Impala to the 'bucket's condition. A good 'bucket is selling for $7-$20,000 depending on engine, dress up and overall condition.