The handle shaft 42 is seated in a set of coaxial openings 69, only one identified, that are formed in the bearing side walls 52 and bearing intermediate webs 66. Ball bearing assemblies 70, only one identified, are fitted in the openings 69 around the handle shaft 42 to provide a low friction interface between the handle shaft 42 and the handle box 50. The bearing side walls 52 and intermediate bearing webs 66 are further formed with a bearing bosses 71, only one identified, in the form of a raised ring shaped rib that extend around the openings 69 adjacent the bearing assemblies 70. A pair of raised riblets 72 extend outwards from the bearing side walls 52 and the bearing intermediate webs 66 between an opposed point on each bearing boss 71 to the strengthening flange 65. The bearing bosses 71 and riblets 72 serve to reinforce the handle box 50 around the handle shaft openings 69. The latch shaft 38 extends through two coaxial openings 73, only one identified, formed in the handle box extension frame side walls 68. Ball bearing assemblies 74, only one identified, fitted around the outer perimeter of the openings 73 allow the latch shaft 38 to freely rotate. In alternative embodiments of the invention, bushings formed of low friction plastic such as Teflon® or Karon® may be fitted over the shafts 38 and 42 or in the associated openings 69 and 73, respectively, so as to provide the desired low friction interface.