Need advice - Exhaust

[Defected]

Hey guys,
I have a 2.5Inch Lukey cat back exhaust on my 89 sedan
Took it off a while ago whilst doing my transmission, Noticed that the cat has been punched out and im pretty sure that my rear muffler has collapsed as the exhaust note is a bit metallic and has a weird muffled oise compared to other V6's ive seen.

My query is.. Should i get a highflow cat and new muffler, replace the cat with 2.5inch piping or leave the cat as is and get the muffler checked out. had various people give me these options. just want to know what other people have done and whats been effective.

Cheers.

[LordMayhem]

replace cat with a hi-flow (as putting pipe through it is illegal) and just get another 2.5" cat back system off ebay whole lot will set you back round 400 i think.