Being you have an automatic car I would go with the 275/50 drag radial. Plus it's much more forgiving in the rain.
You might have to tap on the inside of the wheelwell a tad to get them to fit ok though. It's easy. I had to do it with my 275/60/15 BFG Drag Radials.
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1988 Mustang GT
12.0 @ 122
1992 BadAzz Wrangler
1993 Explorer