I found a 303 with carbed 454 mags I kinda like. However, it does NOT have the original silent thunder box. The straight pipe sound won't work for me. In order to pursue this boat deal any further, I need some more info on how
hard it will be to find and re-install the original ST box. Can anyone help me out with this? Also, will the box from a 336 or 382 fit the 303 and vice versa?

Just add mufflers or go with baffled tips. People pull those f'ing POS's off for a reason. You can't give them away. Most are cut up and burned.

I read this everywhere. But why? What is wrong with them? To me they look much better than a pipe swim platform and they continue the styling of the boat. I have found mine very handy for keeping coolers on and getting on and off the boat.

The box on a 303 is not also the swim platform like on the older Formulas. It bolts on the underside of the built in swim platform. They rattle and sound like crap. Much cleaner setup with the box removed. One of the first mods my buddy did with his '96 303.

How much quieter are the muffled tips/baffles compared to the box?

I totally agree. On any of the SR-1 Formulas, I hate the pipe platforms too.

Corsa baffled tips are pretty tame. Mufflers can be as quiet or loud as you want depending on what you go with. You can find take off baffled tips cheap occasionally online.

The silent thunder on my 303 rattles and it drives me NUTS.

I appreciate all the replies. But the original question still stands. Are the under platform boxes interchangeable between SR and Fastech models?

Let's take it off!!!

I have the silent thunder box from my 303 some where. Nine 7three296112nine