Interior noise level?

[84chevyguyid]

I have an 87 blazer that I am fixing up. Just curious on the noise level inside. I used the stock head pipe and tail pipe but had to redo the section in between. I used a "turbo" muffler and it sounds nice on the outside but its really loud on the inside and has a drone at certain speeds. Just wondering if I went back to the stock muffler, how much quieter would it be inside? Would it help to point the exhaust out the back instead out the side behind the rear tire? I think its actually quieter with the top off

Mike