Abstract: A die assembly includes relatively movable first and second dies, and a plurality of guide pin assemblies mounted on the first die and an equal plurality of aligning passageways formed in the second die for receiving the respective guide pin assemblies. Each of the guide pin assemblies includes a first section mounted within the first die, and a second aligning pin section connected to the first section. Each aligning pin section extends above the surface of the first die for entering one of the plurality of aligning passageways for aligning the first and second dies. Each aligning pin section is detachably connected to a first section and is detached after the first and second dies have been aligned and are ready to be used. In this manner, when the first and second dies are differentially heated during use, the problem of scoring or damaging the aligning pin sections is avoided.