mild and stock lb7 tunes

I was wondering if anybody had some tunes I could try on my truck and then try to teach myself to tune with. Something that won't blow a stock truck. Any help would be awesome! My cousin and I tried some other tunes and it left my trans shifting hard and I need my truck for work. He said he put the stock tune back on but this is definately not stock.
Help please!!
Thanks, andrew

i have a few good tow tunes if your intrested or you can try mcrats 20/20 tutorial

Could I ty the tow tunes for now? Ill ty the tutorial when I get some more free time from school. I'd greatly appreciate!!!
Thanks, Andrew

Any news? I never heard back from you 03 duramax