You didn't mention what year you have. (And you did mention the engine once I read the post a little better.
) The cat plugging is only a problem on 95s (well, at least Ford only has a recall for the 95s).
A Y pipe is a great upgrade from the restrictive stock unit. Keep in mind that there are drawbacks to it - most important the lack of a heatshield for the oil pan that the stock unit has.
