Exhaust systems

I've been to 2 spots, and both have quoted around 1599-$1600. Online searching has shown headers at $600-$700, which is in line with one cost breakdown I got.

I'll hive Hans-on a call.

There are 2 types of headers which are for different levels of performance. The 4-into-1 systems are for high revving (5000)performance, where all 4 of the headers join at one spot into the exhaust system.
The 2-into-1 system with pipes joined in engine fire sequence are better for low range torque 1800 revs up. The pipes are joined 2 into 1 out of the ports and 2 into 1 again when connecting to the y. These sets have the left side 1&3 and 2&4 ports into join into one pipe. They are called interference headers.