how to connect PLL output to default pin

I wanted to add to my original post:

this is a general problem. When you instantiate a component using the megawizard, how can you get Quartus to associate a given instance of a PLL with a physical resource on the target device?

There must be a mechanism, otherwise what is the use of having a default assignment of PLL4_c0 to pin T16, to take the example in my design?

I have poked around in the assignment editor, but even though there is a category labeled PLL, it is empty in my case. I must have missed an (undocumented) opportunity to tell Quartus that I am using PLLs on this device...

Please see attached vhdl file ...