I have an '88 gl-10 turbo.

I am not sure if i need a new turbo or just new gaskets??? I installed a new crossover pipe and reused the old gaskets cause I was lazy and they looked good enough to use. I took the car for a test drive down the road and got 8 pounds of boost for the first time ever. As I drove up and down the road, the boost progressively went lower and lower, until it stared to register zero pounds. I checked and there are no more gaskets there except for the inner rings. Could the leaks totally eliminate my boost, or could a piece of the gaskets have blown through the turbo and be stuck in there somehow??

put some new gaskets on and use a torque wrench. it will solve your problem

if you have exhaust leaks before the turbo, there wont be any exhaust pressure to spin the turbo. use some hi-temp silicone(the orange copper stuff) on the gaskets, even on used ones if they are still intact

Any exhaust leak before the turbo will reduce your boost, often dramatically.