Help understanding rear long travel

Im kinda confused on what rear LT consists of. An sua kit i know but what does that include and why is it beneficial? What leafs are recommended? Do they come included with the kit usually? When talking about leafs, what is 62" and 64" referring to? What does installiation require? Welding, cutting? But what exactly? Any other details? Sorry for all the questions but i just wanna learn what i need to know before i buy anything for my truck. Any other advice or links will be appreciated!!

 

The 62 or 64 refers to the lenght of the leaf spring pack. You need to cut and grind and weld do to the fact you need new leaf hangers and shackles. And you would need new leaf spring hangers, shackle perches, u bolts, leaf spring plates, tabs for new shocks and shackles themselfs. and its beneficial because it give you more travel in the rear, better articulation, and prob the best thing more cushion for the pushing