I have an 86 Donzi Hornet 3 with a merc 502, borg warner trans and TRS drive. right now i'm running stock manifolds with 4" thru hulls. It's been very strongly suggested to me to install mufflers if I'm to run the boat where I am...I'm not familiar whatsover with my options, I was looking for set of inline teague switchables, and maybe CMI switchable tips...but how does a captains call diverter thru the the TRS stand up? what all would I need to install that?

Finding the parts to run it through the transom assembly will be hard. You could remove the exhaust cover plates on the transom assembly and have them cut and welded for tubes - I'd just find some slip-on mufflers and run it like that.

How far out do your TRS tails stick out of the transom? Clamp on style mufflers or clamp on selectable mufflers with butterflys are both available.

Rigging up a Y pipe for TRS + the captians call system would be expensive.

I have some Corsa asr mufflers I would sell if you want to go that route . I finally went with captains call. I had v band flanges welded onto the mufflers , and v bands welded onto the exhaust tips so they are easily removable with a clamp . I also have a set of turn downs with band flanges on them . The mufflers are very effective in quieting down the sound . I can post some pictures if you think it might be an option .