pinion seal

about how long would it take for my pinion seal (93 mustang) leak to be fixed or approx how much would it cost.

Are you doing it yourself or having a shop do it? It doesnt take that long, but it does require a few odd-ball tools like an impact and sockets, seal puller and a jaw puller.

I would have a mechanic do it

I'd say two hours labor and $10 for the seal. Its really not that hard.