I have found two possible solutions for what I want to do. First, I ordered a 67-69 Firebird cowl panel. It still has the vents but does not have the indentation that the Camaro has. So I may just have to weld a flat piece over the vent hole and the slight indentation on the cowl hood and it looks like it may work.
However, since ordering the firebird cowl, I found a website that offers the exact look I was going for. if you want to cut down on the welding, the part can be found from alvilauto.com. They make several offerings of cowl panels including one without the vents but still has the indentation and also exactly what I was looking for, a panel without both the vents and indentations. So, if I am not the only one who was looking to do this, check them out.