need help finding the right set of headers for 57 chevy bel air bbc 468 with motor and mid plate lowered 4 inches rear and 2 inches front please help thanks Jay.
A car running a motor and mid plate is usually a pretty serious drag car. You are probably getting into custom header territory with the mid plate as it may get into a conventional under chassis's headers way. A set of raised exhaust port heads, tall deck, non stock engine location, etc, will make the chances of an off the shelf header fitting pretty much nil.
You might be able to get away with an off the shelf set of fender well headers, as they are not very sensitive to engine location, front suspension , or port location compared to a set of under chassis headers. They also won't care about the Mid plate. They do care about front tire height and you will probably have to run a heat shield on your master cylinder.
This may not be of help to you. On my 57 BB wagon I used a used set of headers from a 79 Malibu and cut and moved the last tube on each side using pieces I bought at Canadian Tire. This was the first time doing this. Do you have the opportunity to borrow headers from others to try and see what fits? I don't see the engine plates causing any interference. You're a bit far for me to bring a spare set to you. Have you been on ChevyTalk or TriFive sites? Lots of good info there. Henry