Starting my suspension build on my 04 and would like to use OME kit incl shocks, springs, torsion bars. A local 4x4 dealer is claiming I need new adjustable upper control arms as well and is charging $577 for them. This is my first 4x4 and I dont have the experience nor do I know the dealer well enough to judge how necessary the control arms are. How important is it to replace these as well? Appreciate the info.