No prob on the spelling. You really don't gain a lot from 4 going to 5 maybe 50* drop in EGT but the sound is like no other. I took the upper bracket off 5 years ago and have not had any probs and I work the truck pretty hard and over 250K in that time over 500K over all. For the most part I did it because at the time no one had done it and said it could not be done. They didn't think I could make a 4 fit back then but I did that to. I put the 4" in in 02 and the 5 in 05. Now with the body lift I think I can make a 7" fit.