Only all 911's you can get rot at around the bottom corners of the windscreen and rear window, as water just sits there, any bubbling here, will mean Window out to fix the rust under the seals..
Also because you do not get any wheel arch liners on a 3.2, both the A & B door posts can seriously rust. And because of this double check the exposed oil lines as these can can damaged and age quickly..
Double get any oil leaks.. [expect a couple], just so you know where they are coming from, some are an easily fixed, or can be lived with.. others require a top-end strip down.. As for a top-end rebuild, then these can be required no matter how many miles, it all depends on what sort of driving has been done...? Motorway [Good] weekend shopping [BAD]. I had mine rebuilt at 78k.
Differences on the Sport models I not sure exactly, however the only ones still left are likely to be interia upgrades.. extra leather & electrics on seats etc... Suspension was originally different, but I am sure it will have been replaced by now [8|]. Brakes were all the same unless you are looking at a wide body supersport which had the Turbos brakes, again spoilers may have been changed and there were also different options here, some had the Turbo lipped rear spoiler, some have the flat sport rear spoiler, others didn't have one.. all a matter of personal prefference. [don't forget it you have a rear spoiler, then there should also be a front spoiler].
Gearbox and LSD... Wouldn't worry about the LSD.. As for the G50.. then this appeared on 1987 models, so it should have one. [My 1987 D has one]. These are fairly bulletproof, but do have an upgraded Clutch Fork & pin and Guide Tube available, which should have been fitted if the clutch has been replaced by a Porsche Specialist.
Good hunting.. It will be nice to see another 3.2 on the streets of Leicester.
Adam.