Nix that aftermarket aircleaner, it only reduces the air pressure differental which decreases low end power as well as let more dirt into the engine. Being in Ca with ultra strict emissions, your options are very limited, that aircleaner would fail right away. Even with LS swaps, used junkyard ones would be illegal, only highly expensive EROD LS crate engines would be allowed for LS swapping in your state. You won't be able to delete any of the emissions. There are a lot of CA LS swap horror stories on LS1Tech.com.
Looks like you have a LG4 305, hopefully a 85 or later one with better CR. Best bet is try to upgrade it to HO L69 specs. Emissions don't really hold the stock engines back, its the tune, low CR on some, cam, restrictive exhaust, transmission tuning, and rear gearing. You could also get a Vortec 350 with a Qjet intake, install the 305 emissions on it and most inspectors would never know. Remember, its not just the engine, but the whole powertrain.