What i know of spoofing is that it will get you banned but you are already with that xbox so that's not of your concern. Second, updates and stuff won't work good or not at all so that would be a reason not to do it either. I guess some other members can find you more reasons not to spoof, so in general it's a big No No. If your dashboard can't be updated, then you will not be able to run a certain firmware in one moment, what will cause you not to be able to play some of your backups anymore in the near future.
But if you really want to do it, you will need to use your key FW from your benq in source and the target will be also benq firmware LT+ 1.91, this will (with your LiteOn connected) spoof the LiteOn with the benq firmware. That is if i get your post correct. You can see for flashing the tut in my signature, they don't show how to spoof, but writing the firmware is pretty much the same as if you were using a original benq drive.