NCRS judging manual says the following on L82 carb part numbers:
L82 w/auto no AC #17059210
L82 w/4-sp manual #17059211
L82 w/auto & AC # 17059228 (this is what my L82 has)
Also, look at intake manifold. For L82 application, part number should be either 458520 (early prod) or 14007378 (late prod). It should be painted a silver color and it is made of aluminum, not cast iron like on the L48.
The L82 value covers are black, silver finned in design and are aluminum too. There should be a cross flags emblem on the passenger side cover. It sounds like you have after market valve covers.
Just because your engine doesn't have the AIR system on it, doesn't mean it isn't an L82. Most owners removed them and plugged the holes in the exhaust manifolds. You really have to get a clean look at the engine stamp pad on the passenger side of the engine, forward of the cylinder head. It should look something like this: (as detailed in the NCRS judging manual)
V0302ZBB (automatic example only could be ZBA for 4-speed also)
19S4xxxxx (where the x's are the last 5 digits in your VIN)
Use some degreaseing agent to clean the pad, as it might make it easier to read.
Hope this is as clear as mud!