Spent a lot of time fine tuning the fit on the inner cowl. You can see where I've cut the bottom off to simplify the fitting. The shape of the bottom was way far off and making things too difficult. Since I won't be replacing the floorboards until after the doors are hung, I'm just going to shape the cut off part to fit whatever gap I need to fill between the floor and the inside cowl.

After looking at the initial fit again I decided to drop it down about 1/4 inch which eliminated the problem of the reinforcement beads not lining up with the channels in the inner-to-outer cowl panel.

I also want to keep the Fresh Air heater blind nuts so I plan to weld the new part to the old. Hopefully this will make locating the heater simpler. I spent about an hour test fitting a spare heater and things are close enough so that I'm not worried that I'll need to do surgery to get it in... he said optimistically.