2002 dodge neon

Couple of questions 1. What size are my
sway bar link I've seen 20 mm and 22 mm I
have no idea what size they are 2. I have a
sound coming from the passenger side of
my motor it sounds like an exhaust leak
but I have searched everywhere and I have
found no kind of leaks anywhere I have
changed my exhaust manifold gasket and
the sound is still there I do have to change
my upper and rear motor mount my uncle
has said he thinks its belt noise but I still
think it's an exhaust leak please help