How do you pop off the top plastic piece on the dash and is it easy to replace.. Mine is cracked...

 

If it's already cracked you shouldn't worry about how to remove it, just get it out, and notice where the tabs are, then when you get the new one in be extremely careful putting it in! I heard they are pretty cheap and come in a sturdy box since they are so flimsy and breakable. There's another thread here somewhere about it, you should try a search for it.

 

you'll need to remove at list one a-pillarit's easy to do with the t-tops if you have them.
then just pop up the peice which holds by the some sort of a velcro. takes about 5 minuts.