One difference at least is that you will not need an adaptor plate as the ITBs are a DCOE pattern and can bolt up to a lot of commonly available triple carb manifolds.
I need an inexpensive set of standard bore L28 flat top pistons. Let me know what you have. Local to the PNW (Portland OR) would be great, but not necessary. Thanks for looking.
Valve cover looks great - they did the wrinkle finish on the turbo, can't go wrong there! I think doing the stock airbox would be awesome, I don't believe I have seen it done before.
They usually have one price for a complete long block engine w/no transmission, torque converter, etc. and then individual pricing on all the pieces if you buy them seperately. You are almost always going to do better buying the complete engine if you need more than one major component from it.
It varies from car to car. Some people have made a 2 seater driveshaft work without shortening, others have shortened up to 1". You need to measure it for your car.
The shape of your lenses lead me to believe that they are probably originals, and not reproductions. See the following picture. The OEMs follow the line of the car like yours do, the repros do not.