2nd Gen Non-Engine/Transmission Gauges bouncing

[sevobuck]

I installed two Autometer Phantom series gauges in my truck. One Pyro and one Boost. Under a boggish accleration (say going around a corner in 4th and then acclerating) the boost needle jumps as it rises in pressure. It will not do it under fast and proper acceleration though; nice and smooth and normal. And sometimes my Pyro needle vibrates up and down when sitting at idle for an extended period of time (10 minutes). Any advice? Thank you