The following code compiles and correctly resolves the lvalue vs. non-lvalue overloading:

import std.stdio;

void doStuff(const ref int i) {
    writeln("Doing stuff by ref.");
}

void doStuff(const int i) {
    writeln("Forwarding to ref overload.");
    doStuff(i);
}

void main() {
    doStuff(1);
} 

Similar code also works for classes and arrays.  It seems to be broken for structs, though.  The following code is rejected:

import std.stdio;

struct S {}

bool fun(const ref S rhs) {
    return true;
}

bool fun(const S rhs) {
    return fun(rhs);
}

test9.d(12): Error: function test9.fun called with argument types:
	((const(S)))
matches both:
	test9.fun(ref const const(S) rhs)
and:
	test9.fun(const const(S) rhs)