Don't want to pour cold water on your optimism but before you do anything I would recommend you have a more thorough examination of the shell. If the visible items are shot as you suggest then there's a fair chance the usual hidden Z nasties are going to rear their ugly heads. Take the front outer fenders off and check the "tubes" that run on top of the inner fender. Check the inner fender itself for rot. Thoroughly check all the frame rails, inner sills,trunk floor, inner rear fenders. There are others but that's enough for now! A lot of these items are no longer available and you may find out your patches are bigger than you anticipated! The reason for my apparent pessimism is that here in the UK we have pretty similar road conditions and nearly all our Z's have had extensive body rebuilds.