Where can I find tuneup specs for 1970 402 (LS3)?

[davepl]

My rebuilt engine is on the dyno, and I'd like to find the original tuneup specs for the 1970 402 w/TH400. On the dyno they're having trouble getting it to idle below 900 (all stock) and I'm pretty sure the stock idle speed is much lower than that.

On the cars there was usually a sticker on the rad support with timing and mixture settings and the RPM in drive, etc. But my truck doesn't have it, and I cannot locate it in the owner's manual nor the service manual.

Can anyone point me to where I can find the "official" tuneup settings?

Thanks!
Dave

[davepl]

FWIW, I found my reproduction of the emissions decal that says 600rpm and 4' BTDC, so that's a start. But if there's a canonical section in any manual with all the specs, I'd still like to find it.

[ToddT]

Does this help, my truck is a '71.

[Lee H]

Directly out of my Chilton's manual, 8 degrees before TDC @ 600 RPM, in drive.