Disclosed herein, amongst other things, are various conversion structures for use in a molding system (100, 200). A non-limiting embodiment of the conversion structure includes a standard mold receiver (140, 157) and a mold conversion module (151A, 151B, 151C, 251A, 251B, 251C, 251D, 251E, 251F, 152A, 152B, 152C, 170A, 170B, 170C). The standard mold receiver (140, 57) and the mold conversion module (151A, 151B, 151C, 251A, 251B, 251C, 251D, 251E, 251F, 152A, 152B, 152C, 170A, 170B, 170C) are configured to cooperate, wherein the mold conversion module (151A, 151B, 151C, 251A, 251B, 251C, 251D, 251E, 251F, 152A, 152B, 52C, 170A, 170B, 170C) is receivable in the standard mold receiver (140, 157) for converting a molding configuration of a mold (120).