I have an LS6, which had a couple of camshaft lobes go bad. Probably from a previous owner not using a proper oil with the ZDDP additives for some time.
As the camshaft was removed I had it evaluated, along with 3 NOS GM 3904362 cams that I have bought over time. The cam out of the car and one of the NOS cams was sent to Competition Cams for measurement of specs. I was quite surprised to find that the original cam did not measure the specs for an LS6. The NOS cam does have specs very close to what is published in various GM literature for LS6.
One of the NOS camshafts, along with a set of NOS 5232695 lifters is going back in.

My question is how do I know if the valve springs are original correct ones for an LS6? Are there some specifications I can check?

Thanks.

I was able to get the answer on the NCRS.org web site. Thanks for anyone who viewed my question and was looking into it for me.