Getting into Tokyo from Narita after arrival

I have following questions:
Am landing at Narita on a Monday at 15.45 hours (3.45pm) local time.
1. How long will it take to clear immigration and customs?
2. I need to go to Shiba Park hotel in Shibadaimon near Tokyo Tower. What are the best options other than hiring a cab?
3 . If I take the train is it very difficult? Especially with our luggage? Where do I board and which station do I get off to reach the hotel?

Customs/immigration typically 40 minutes. Range from 15 minutes to 90 minutes (longest reported case from 2018 was three hours).
Train is easy - head to basement level to get tickets - station is in the terminal. Only people with money to waste get a taxi.
Train routing - check http://www.hyperdia.com/en/
Bus might be an option.

If you can catch this bus, it will be the easiest way.

https://www.limousinebus.co.jp/en/areas/bus_stop/nrt/shiba_rinkai/dep/...

Unless money is no concern at all, taxi isn�ft a viable option. Narita is far from Tokyo and taxis in Japan aren�ft cheap. They are ok for shorter transportation IF no alternative with a train is readily available but Narita Tokyo.

Train from Narita to Tokyo is easy. https://www.japan-guide.com/e/e2027.html There are two main express trains you can take and google maps or hyperdia can help you with your connection. If you are afraid of your large luggage, either bring a smaller one or if that is not an option bring a small overnight luggage plus a big one that you can send from the airport to your hotel. As you are arriving in the afternoon it will be delivered on the next day to your hotel. You can use such a service also within Japan if you are moving around.

Delivery service is called Takyubin: https://www.japan-guide.com/e/e2278.html

Enjoy your trip to Japan!

Thank you so much.

As already suggested, the limousine bus is probably the easiest (though not the quickest) way to get there, as it will take you directly to the hotel. However, the last bus leaves at 16.25 to 16.40 (depending on which terminal you arrive at) so if you arrive at 15.45, you have only 40 - 55 minutes to clear immigration and customs, get a ticket and get to the bus stop. You may make it but it will be tight, particularly if you haven't done it before etc......
https://en.shibaparkhotel.com/wp-content/uploads/sites/86/2018/11/Airp...

Believe it or not, the hotel website has directions on how to get there ....
https://en.shibaparkhotel.com/location/

As suggested by the hotel website, the Keisei Skyliner to Nippori (and then the JR Yamanote line to Hamamatsucho and a short 8 minute walk from there to the hotel) is the quickest. The Skyliner has departures at 16.02, 16.22, 16.42, 17.02, 17.22, 17.43, 18.09 etc.

Thank you so much