The following 911SC site also has gobs of info on the sc models.
Simon's Porsche 911 SC Site
I too just recently purchased my first Porsche which is a 1983 911SC, but I researched and looked every day for hours and about 11 months later I found the perfect one. So my advice is to be PATIENT and not jump into a lemon that will cost you more in the long run. As many have said a PPI is a must and possibly take it to two or more different Porsche reputable shops to get different opinions and insight.
The search is a lot of the fun part so enjoy it! Good luck.
James