Forming First Exhaust Manifold Shell Half

 The rain stopped but it is very humid.  I worked until I couldn't see for the sweat on my safety glasses.
The first step was the same as forming the elevator horn.  I started with the narrow tool on the rivet gun.  The idea is to get the bend started without creating wrinkles in the corners.  I started at the corners and worked to the ends of the pipes.  I didn't do the long edge at the bottom because at this point I just want it to let the steel slide toward the inlet ends.

 Next I used the trailer hitch ball to work the pipes.  I t looks a little rough but it will smooth up easily with the rivet gun.  You can see a bit of a wrinkle forming where the 2 forward pipes join the collector.

Next I used the rawhide mallet to start forming the collector.  It looks very rough but it will smooth out as I work the metal.  At this point I realize I need some gauges to make sure I form the pipes and collector deep enough.

I did a little smoothing on the right hand (forward) pipe.  It will all smooth up very well.