C# creating an implicit conversion for generic class?

I have a generics class that I used to write data to IsolatedStorage.

I can use an static implicit operator T() to convert from my Generic class to the Generic Parameter T

e.g.

MyClass<double> foo = new MyClass(187.0);

double t = foo;

My question is, how can I do the reverse?

MyClass<double> foo = new MyClass(187.0);
double t = 0.2d;
foo = t;

The implicit operator has to be static, so I'm not sure how I can pass in the instance of my class?