2000 engine in a 1999, any issues?

I'm not sure what engine size, My mom rolled her 2000 jeep grand cherokee and I think it has a 4.7L, but the car is totaled. But she drove it out of the ravine and it was running fine. So the engine tranny and 4 wheel drive still work fine.
She's found a 1999 grand cherokee with a blown v8 engine. She's planning on buying that jeep and puting her engine into the old one. My question is will the 2000 engine match up with the tranny and will all the electrical be the same?

I'm sorry if there's another post related to this one but I'm short on time and I have to leave in 2 minutes and I would like to provide her with some accurate information sooner rather than later.

Thanks in advance

The 4.7 will swap between a 99-02 (02 non HO). 03-04 you need to match tone ring teeth.