The key is to take your time. I've driven my car through 3 winters and have not gotten stuck (unless you want to count the one time I was plowed in due to the snow removal people). I use 245/60/15 Cooper Cobras in the winter and they work fairly well. I don't add any weight to the trunk either. I do have my battery in there, but that is for racing purposes.
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1989 lx notch
89,000 miles
bolt-ons,stock heads/cam
60'- 2.07, 8.90@78, 13.93@99