Yes. It says in description
If your lower receiver accepts mil spec AR15 fire control groups, it should fit. Removal of the safety and grip may be necessary. Make sure to check safety function and reset. I'm certain O.P. will take care of you if you have issues.
Per the product description, yes.
yes, it will work with an AR10 build
he MBT-2S can also replace the stock trigger on any mil-spec AR10/AR15 lower receiver.