No
700 ADL Long Action
no there are some minor adjustments to the safety area
No, the Remington Model 1100 stock has a hole (recepticle) through the inside of the stock in the pistol grip area to accept the action spring tube. The Remington Model 870 stock has no need for this hole so the 870 stock will not fit on the Model 1100 action.
Timney makes a great aftermarket trigger for the Remington model 700,that will fit your Remington model 722 rifle.
Assuming the Remington SPS Tactical you are referring to is chambered in either .223 or .308, yes the SA (Short Action) stock will fit.
No, Winchester 1400
Yes, The receiver pins are the same as the Remington 870, so any stock that will fit the 870 will fit the 7400
yes a BDL rifle will fit a ADL stock but the trigger guard will not but a new trigger guard can be bought for 20 to 50 dollars and brownells.com
NO
No, the re4ar receiver face on the Model 11 Remington has a different configuration. The Remington Model 11 is a semi-auto with a tube containing a bolt return spring located at the rear of the receiver. The Model 11 stock has a receptacle to accept this tube, the Model 870, being a pump action, does not have this receptacle.
Yes they are interchangable.