I can't help much with the Gen I Solara but on the Gen II (2004 and later) all you have to do is push back the tab on the lens (frame) covering the bulb and lift the lens away. Then turn the bulb...
gently insert a small flat head screwdriver on the left side of the bulb plate a push to the left.... the entire should bulb frame will shift to the left and then you can pull the frame out to...
It is NOT illegal to mount your plate vertically in Ontario Canada. I got this right from the OPP traffic manager by contacting them through their web site:
Section 13 of the Highway Traffic Act...