good evening this is my first post here and I'm from south Mississippi just wanted to start this with a question. I bought my first Tahoe a week ago, used 190k miles. It's mint on the exterior and interior. First thing I noticed was an oil leak that was diagnosed as the rear main and my mechanic is telling me he believes the crankshaft has to much play and is just gonna continue to wear the rear main. I mentioned this to the guy I bought it from he was in no way at liability to do anything but I knew the type of guy I bought from. He said instead of tearing the motor down to inspect that crankshaft and replace a rear main let's look at a new/reman motor. With that said through my dad's work, 25 years owning an auto parts store I can get a full 5.3l for 1812$ that's tax included. 3 year warranty or 100k miles. Now at a 190k miles this seems like a deal I should go ahead and do. Because the interior and exterior are to mint to just salvage over motor isssues in my opinion. Now to the question, I'm looking into a CAI, muffler and tuner as my first three purchases to go on during installation. This is gonna be a family vehicle with the side of being my toy sometimes lol. So I am not gonna do a full loud exhaust. I was thinking a 50 series flowmaster muffler, volant cai and not sure on the tuner. Suggestions??? The current motor that's in it runs at idle and 40 pounds of oil pressure and runs at constant 50. Hate to just let it go but if it's gonna cost me as much to fix it as a replacement would cost it's worth it!