This is a complete bolt in kit for intalling a modern booster and master in 1957 and 1958 Cadillacs that retains the heater function. I don't have any installed pictures yet, and that is the reason that some of the pictures show the non heater version of this firewall palte. The air duct opening is in the same same position and is the same diameter as original. This kit uses a modern power booster and dual circuit master cylinder mounted to the firewall using the bolt holes for the factory air box. It includes a new brake pedal that swings from a different location (looks like it could be original too). A modern GM booster and master cylinder give a significantly improved braking feel and power while adding safety through the dual circuit system. It will have the pedal feel of a modern car- minimal effort required with a positive and firm feel. No more soft or sloppy pedal. 
 
This can be used with factory drums, disc/ drum or disc/ disc. Let me know what brakes you have at check out and I will send the correct proportioning valve. 
 
Installation is fairly straightforward- likely no cutting required, this kit doesn't involve anything permanent that can't be undone in a couple hours! You have to remove the driver side air box, vent door, master cylinder, master cylinder mounting plate, and then this kit bolts in. Brake lines are included and pre-bent but the rear line will require you to splice in to your original system. Installation time is about 4 hours. 
 
This kit comes with everything including proportioning valve, brake lines, and hardware! All you need is brake fluid and a port on your intake to plug into vacuum. 
 
Also, you will have more room in the valve cover area that the original air box. so it clears all original engines just fine, and will provide additional clearance for vehicles with a swapped engine. 
 
The firewall box has water drain spouts and new drain hose is included. water will be able to drain out from the windshield area just as factory. 
 
 
What you get: 
Firewall box with heater vent opening 
Brake pedal bracket, goes through air vent hole 
Brake pedal W/ Bushings and rubber pad 
GM style brake booster
GM style master cylinder 
All new high quality bolts 
2X 3/16" brake lines- custom cut, bent, and flared
Proportioning Valve + metal lines (mounts beneath MC, pictured)  
3/8 Vacuum hose
Water drain hose, same style and function as factory 
Misc. hardware 
 
Brake Booster and Master Cylinder come in either zing/cast or chrome finishes. 
 
All metal parts are CAD designed, laser cut, formed on a computer controlled press brake, professionally welded, and painted satin black for consistent high quality results.