Call me cynical, but I believe this is not possible. It may be upgraded, rebranded, recertified, and they may retrain everyone who may come anywhere near its cockpit, but they can't just drop the plane for three reasons:
1. They already sold too many. Those customers will want a refund, and will have a major loss of faith into Boeing. Unless there is a replacement plane to give but ...
2. They don't have any replacement. They don't have anything to put in that slot. And it's already a plane they had to rush because a) it's the main seller, and b) the competition (A320 Neo) is a very good plane in that slot.
3. Like said above, it's the major seller. It has how many thousands of orders and how many years of wait to get your planes already ? And nobody cancelled to move to airbus because they're just as backlogged. So neither Boeing, nor the airlines, nor the US government want it / can afford for it to disappear, they want it fixed, anyway possible.
Don't get me wrong, I believe in a perfect world it should be grouded forever and be remembered as a huge warning lesson, but this will never happen.
The real question is, why aren't Airbus and Boeing massively increasing their production capacity for those lines ? Feels like they've been been backlogged since forever, and it's only getting worse. I get that you can't create a new set of factory and their trained workers overnight, but we're talking decade here.