John,
If it is the original muffler, it should be a straight-thru, but I would check on it to make sure.
If it doesn't sound like a throaty V-6, it would be a tell-tale sign.
But if you do need a muffler or change to duals, I don't believe the original V-6 muffler is still available. I know that the pick-up muffler has been dis-continued for years.
You would have to go to a glass pack of some type. I would use ones of the same length and would make sure that you can see right thru them.
Duals will make a difference. Sound better too.
Bill
