Is there any way to combine these almost identical classes into one?

Followup to this question: Why is Nullable<T> considered a struct and not a class?

I have two classes that essentially maintain a tuple of some user-supplied value with an internal object.

When the type of the user-supplied value is a primitive, I have to wrap it in a Nullable<T> so that it can take on a null value in the Tuple.

public class BundledClass<T> where T : class
{
    private Tuple<T, object> _bundle;
    public T Value
    { 
        get { return _bundle == null ? null : _bundle.Item1; }
        set { _bundle = new Tuple<T, object>(value, internalObj); }
    }
    //...

public class BundledPrimitive<T> where T : struct
{
    private Tuple<T?, object> _bundle;
    public T? Value
    { 
        get { return _bundle == null ? null : _bundle.Item1; }
        set { _bundle = new Tuple<T?, object>(value, internalObj); }
    }
    //...

I'd prefer it if I could do this with a single class that can take either primitives or classes as a type parameter, but I don't see any way around it. Not without coming up with some sort of custom Nullable class that can box any type (not just types where T:struct) so as to ensure that Value can always be assigned null;

It seems like I should at least be able to define the latter class as

public class BundledPrimitive<T> : BundledClass<T?> { }

But even that fails since Nullable<T> does not meet the : class constraint (as per the linked question).