Voodoo13

I recently purchased a 72 240z, knowing there were more than a few bugs. I have a few that I am hoping some of you have input on or experience with. Behold, the list: 1. Electical: The stereo (and usually headlights) go off (briefly) when hitting a large bump (especially when going slow). This appears to happen when braking at times, also. A simple short in the system or part of a larger electical problem? The stereo always turns off when the hazzards are on. 2. Engine (oil): the pressure guage can, at times, go all the way to zero, when idling. Seems to be okay (relatively) when driving at various speeds. There is also an oil leak that is more significant after longer drives ... appears to be coming from area where transmission meets up. 3. Engine (temperature): Though there is plenty of liquid in radiator, longer drives on freeway result it temperature guage going and staying over 250 on guage. Obviously a problem, but not sure to what extent, considering possible innacuracies of older guages. Despite the level, the engine does not overheat in a traditional sense. Thanks in advance for any advice on these items.