DX MC-E modifying for direct-drive?

I'm not very knowledgeable about this, but recently opened up a defective drop-in to see how it's all arranged.

I don't like modes, especially strobe. And I have read many times that the DX MC-E's driver board underpowers the LED. First thing I thought was instead of getting a different driver board, why not just wire up the + and - directly to the power source?

I can't find a real answer about the max voltage of the MC-E itself, and whether a 3.7v 18650 charged up to 4.2v will ruin it.

Does this also mean it would be dimming the entire time, up until the protected battery cutoff? Still better than having it dim the whole time, due to the bad driver circuit.

I keep seeing the stars and everything on DX that are too big at 20mm. Good thing I have this donor drop-in.

EDIT also reevaluating doing the whole thing with my R2 since I have the 'new'/crap version of the good old R2 board from DX.

I think I read recently that one 18640 will fry an MCE unless you get one with sufficiently high Vf. You could always ad a resistor to the circuit though.