To get the old roller off I pried the spring off and then pried the old roller off. The new one i got from the dealership is hard to get on there. Any tips or tricks?

I did not take the door off to take off the old roller, do I need to take the door off the put the new one on? It comes with a plastic sleeve already installed inside of it. Woudl I need to grease the inside of that plastic sleeve?

 

TTT

 

I fought this battle some time ago. Basically, yes, you do have to take the hinge off in order to reinstall the spring. At least I did, I fought that freakin thing for hours until I gave up and removed the hinge. This is what worked for me:
Get a floor jack and place it under the door to hold it up, have someone else help if possible.
Disconnect the hinge from the body portion of the car. In my car, two bolts went into the hinge from the outside, (the new hinges delete one of these holes) they are a pita to get to with a wrench, so when I had them out, I cut a groove into the head so I could get a screwdriver on it from the INSIDE and screwed it 90% of the way in that way. Then I just needed the wrench to tighten it.
Anyway, with the hinge d/c'd from the sill, you can completely assemble it on the door, then you just bolt it back onto the car. You can sort of use the door as extra leverage if needed, but be careful, you don't want to bend anything.

 

There was one occaision where the spring was collapsed in a vice and then a wire was run through it to keep it compressed. Then the wire was cut when the spring was centerred. I tried this several time w/o good results, but maybe you'll be luckier than me.