my thruck started out as a base 4.3l 5 speed reg cab work truck 2003. I am in the prosess of swaping my 6.0l now a 6.6l into it . I need to know what kind of rearend it has on it there is no tag for some reason. Bassicly I need to know what this axle will hold up hp wise. and what kind it is . My truck is bagged so there are brackets welded onto the housing so a swap isn't really a good idea HELP!!