Any NAPA or other reputable parts store should be able to get you the part number. Go in and descibe exactly where it's located, they can probably pull up online diagrams that show the configuration of the line so you can see it and match the length and bends to yours.
Not sure if a '91 is different than a '95 in this regard, but my tranny lines have the conical ends with the plastic inserts in them. You push in the two tabs on the plastic insert and the line pulls straight off. There's probably a tool for it, I just used two small standard screwdrivers, one on each tab, pushed in and tugged the line while holding one driver in with my pinky finger.