Direction of train and baggage size

[eaw]

Hello:

My husband, son and I will be traveling from Dublin to Limerick on Saturday, July 3, 2010. I am planning to buy standard seats online and want to know which direction the train will be traveling so that I can choose 2 seats facing toward Limerick. Does the locomotive always face the direction it's traveling on the seat assignment page? Is it worth it to buy premier seats?

We will have 3 large (30") suitcases with us. Is there a size limit to the baggage you can travel with? I found the weight limit, but no size info. Where does the luggage get stowed since they will be too big for the overhead bin? Will we need to carry it on board ourselves?

Thank you so much in advance for your help,
Esther