Possible causes of my boost gauge to go crazy?
Reads vacuum just fine. As I go into boost it starts fairly steady but as RPM increases, the needle bounces around like crazy!
I've confirmed BOV operation.
Wastegate has been removed and disassembled for inspection. I changed the spring to be sure that wasn't the fault. Also checked operation with air pressure.
No vacuum leaks.
Charge pipe and carb hat are sealed.
Everything is tight.
I'm at a total loss!!!

Does the engine feel like power is doing the same thing?

I'm not entirely sure, Tom. The car still pulls quite hard. The engine sounds normal for what I can hear.

The placement and type of BOV can induce the problem you describe. Sometimes it is merely solved by joining it with a smooth transition pipe instead of a Tee.

If it started out this way, I'd look a lot harder at that... this is a new happening. Only within the last week or so. I've not touched the car, aside from trying to figure this out, so I'm not sure what has brought it on.
Could a worn valve guide cause this?

If you trust your gauge is working properly and everything is tight I would lean towards the BOV as Frenchtown Flyer mentioned if the engine seems to follow the gauge. If it's just flutter in the gauge maybe try a liquid filled one.

I DO have a liquid gauge I was going to use for fuel pressure... I could plumb it in to confirm. I hadn't considered using it for this purpose.

What range is the bounce? Is it a lb or two? What engine speed is it showing up at? Does it flutter all the way up to wastegate opening?

This is no longer a concern for me... the car was traded last Friday. For a 55 Belair. It currently has a late model SBC, which I will be removing and installing the turbo 250 I've been working on for the Nova. Bit backwards, but I love the 6s!