Please Help me identify the CNG system installed in a recently purchased truck.

[Keith Snell]

We just purchased a 2006 Chevy Silverado (4.8 Vortec) that was previously modified as a bi-fuel CNG vehicle. The truck runs great on gasoline, but stalls when switching to CNG. Unfortunately no documentation came with the truck so we don't know where to start troubleshooting. If we could determine the manufacturer/installer of the CNG system that would give us a good start. I'm posting pictures of the system in the hopes that someone can point us in the right direction. Thank you!
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