The reality is that not all tires fit all rims even if they are "supposed to fit".

You can try soaping your tire and rim to get the tire on - with levers, of course. I use metal tire irons instead of plastic when the going gets tough.

Changing a tire isn't rocket science. Either it fits or it doesn't. If it takes you 25 minutes to get the tire on, then bring the tire to the LBS where you bought the tire and see if they can get it on for you. If not - pass and get a different tire. Ask yourself how would you like to do a flat repair on the road with that tire?" Bad enough when you are at the comforts of your home and well tooled shop.