Sounds like you also forgot about the Rockets/Magic sweep, as well.
I'm thinking back, but I can't think of any time in the 90's where both road teams in the Conference Finals advanced. I'm not sure about the late 80's-early 90's Lakers/Blazers and the late 80's/early 90's Pistons, but I'm skeptical. Other years where it might be possible would be the '86 Celtics/Rockets (although I'm pretty sure Boston was the #1 seed), or the '81 Celtics/Rockets (although I'm pretty sure Boston was the #1 that year as well) and prior to that, it would be the '78 Bullets/Sonics. That takes me back to the start of my exposure to basketball.