Your car probably starts in second gear - they tended to do that in that era on cars with lots of torque. But as I understand it your question has to do with manual shifting, and that it operates normally when you put it in drive. If it in fact is operating normally when in drive but won't manually downshift to 2 or B (B stands for braking but it's actually just first gear) there's probably nothing wrong with the transmission itself - only the gear shift or linkage. Failed shifter bushings is a common problem. If you do a search above you find many threads on the subject. The linkage from the gear shift knob to the transmission has two bushings where the rods connect and when they disintegrate all kinds of strange things happen. The bushings themselves are cheap but the job is very tight and something of a nuissance. That's where I would start. The other possibility is that someone has dropped something down the shifter and it is somehow obstructed. It definitely should shift to both 2 and B.