simple, just take the neck and the body apart. the body cavity of the MIM strat should have some barcode like sticker in the middle pickup cavity area.
1.check the serial number on the headstock and do a check on the fender website.
2. Take the neck off, it should have dates and info on the base of the neck where the 4 bolts screws are. dates / model
3. check the body of the guitar for the same. some are on the 4 bolt screw area and some have them in the pickup cavity. it varies for different models. Some even have a sticker type indication under the pickguard if its stock.
4. try summing all the data you can collect from the few steps to see if the info on the fender website matches the model and year.