You can get slide-on adapters that basically clip onto the IBM rack that
provide the nut. Example:
http://www.blackbox.com/Catalog/Detail.aspx?cid=111,1340,1350&mid=4111
In addition to the IBM 0551/0553 racks, our main data center racks are
like this. Normal racks put the nuts on the rear mounting frame; our
main racks don't have a 'front' or 'rear'. The mounting frames are
fully moveable to wherever works best so the racks can accommodate
odd-depth equipment. And without the front/rear concept they don't have
pre-mounted nuts.
As an aside, don't forget your PDUs. You don't want to overload the
power draw. We started with 2 PDUs and went to 4 when we went above
half-full. Everything that can use redundant power does.
