Got some more body work done:

Patch panel ready for some primer to hold it over until Spring:

Fabricated a piece to hold a plug I patched:

Clamped it to the firewall bracket:

View from inside ready for patch piece:

Fabricated plug:

Clean the metal for welding:

Place the fabricated plug in to but-weld:

Fabricate another piece for a lap weld:

First pass at welding:

A little grinding:

Lap weld other piece in:

Grind the welds down:

The piece is not flush with the car, so I decided to fill it in with more welds:

More grinding shows some more welding was required:

View from other side:Treated the metal with Eastwood Metal Prep – will shoot some primer this next week.  Bought a dehumidifier for the garage which should help.