I used some cardboard to make patterns for the openings in the cowl for the windshield wiper pivots. Once I had them fitting well, I taped them in place beneath the cowl and marked their position. I cut the openings in the cowl and transferred the pattern shapes onto some 20 gauge sheet metal I'd bent with my son's brake.
I have been considering how to support the edge of the cowl cover beneath the windshield for several months. Yesterday, inspiration grabbed me as I pilfered the scrap pile: the A-pillar from the 2001 Malibu has the perfect shape for brackets. I cut seven one-inch pieces from the A-pillar and made some mounting plates from some 18-gauge scrap. I cut vertical slots in the mounting brackets, welded the plates to the brackets and screwed them into the firewall. The slots allow adjustment to hold the cowl cover against the bottom of the windshield frame loosely enough to allow me to slide it into place, making it removable.
Welded the two pieces of door skin together and extended the trailing edges with some pieces of the bed side I used to make the grill shell. Used the first cowl cover attempt as a pattern to mark placement for the wiper pivots and their brackets. This one went a lot faster than the first attempt.
The welds are much better after I reinforced the mig welding gun hose where it exits the machine with a six-inch-long piece of rubber hose and a large piece of heat shrink. The gas hose was being crimped and gas flow to the nozzle was apparently compromised. Now, my tacks are 98% good versus 50% suffering severe porosity before the fix.
'Might work' is the key phrase. The driver's side end of the rolled bead was too long and extended into the fender. My fault; I should have measured with the fenders mounted before sketching out the bead. I tried removing a one-inch piece from the bead, but my welds were pathetic. Between the porosity in the welds and the marks from hammering, I decided the piece was junk.
Rather than try to reproduce the flat piece with the bead, I am trying something different. I have two curved pieces left from the tops of the extra S10 doors I skinned to fill the wheel wells in the front fenders. I'll have to extend the back, flat edge of the pieces to make the pieces work, but I am going to join these pieces for the second cowl cover.