You can check the registry programmatically (like any COM server, not only .NET), for example, here is what produces the regasm for a class named net2.Class1 in an assembly named 'net2.dll", that was registered with the /codebase argument:

For a non .NET COM Server, the important part is the default value of the HKCR\CLSID\<your CLSID>\InprocServer32 key which points to the dll that exposes functions to create the declared COM objects.

For a .NET class, this value must be set to mscoree.dll (which is part of all .NET installations), and then what's also important is the keys Assembly and Class.

Note I have provided an equivalent sample of RegAsm in C# code here: Registering a COM without Admin rights, you can also use it the other way round to determine what are the important keys.