How about a block of wood against the passenger seat and a block against the rear seat and put a small hydraulic jack between the wood and pump it and at the same time pull up on the seat end to get lift over the tab. might work?
You shouldn't need to do that. If you do you could damage the frame pretty easy since it is pretty light. While I haven't done one on a fastback the rest I have come accross is just a strong shove back and lift at the same time.