Sounds like you have:
Products-General ... don't display inventory.
Products-Inventory (was products-music) ... DO display inventory count.
THen you have categories, with restrictions such that when you create NEW products within those categories, you can ONLY create those NEW products based on the restricted choices.
It doesn't affect existing products.
Further, using the method you've selected, IF you created products using the "products-inventory" type, you'd end up with URL's looking like:
index.php?main_page=products_music?pID=12345
or, if you also changed the page_handler setting, you might get:
index.php?main_page=products_inventory?pID=12345
... but you'd likely also get numerous other errors, because you likely didn't program all the other requisites for product-type support for the renamed handler.
So, rather than depress you ... can you please explain what sort of pattern/logic/rule can be used as a common denominator in choosing whether to display inventory information.... so that another approach may be suggested.
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