Pants and prim question

I suppose this is a question about skirts, too, although I haven't attempted making one yet.
I'm making my first pair of pants and I want to give them a boot cut. I know I'll have to make 2 prims to achieve this effect.

Do I link the prims to the pants template (is that possible?). I notice when I buy flared pants with prims, that all I see is the "pants" template in inventory. I do not see a separate object containing prims that I have to attach to myself, as with flexi skirts.

Can someone explain this to me?

There's no way to attach anything to a template. The template is an image file, residing on your own hard drive, for you to paint on. It's not actually a part of the pants.

If you want to attach prims, you attach them directly to your avatar. In this case, you'd attach to the lower legs.

You don't need to attach prims to do what you want to do though. You can flare the pant legs simply by using the sliders. You can do anything from skin tight cuffs to bell bottoms. A boot cut should be well within that range. If you want to put in a slit to see the boots, do that with texturing. Just put a transparent sliver on the template (black sliver on the alpha channel) where you want the slit to be.

Sorry, by template, I meant the pants texture (image, base?) after it had been uploaded to SL.
So the reason I'm seeing pants being sold with no accompanying prims is that the flare effect is all done with sliders.

Thanks Chosen, you've cleared up an irksome mystery for me. Very grateful.