Why do you want the taller sidewall 55 series tires?
More roll over and less handling, turn-in, and steering response.

I would go with the slightly smaller diameter (but wider) 215/50 tire then. Since you ruled out my first choice. (225/50)

2000 SVT #674 - Check it out!

Whoever coined the phrase; "If it ain't broke; don't fix it" ~ Just doesn't get it...