Fitted the top and bottom cowl to the firewall with the Skybolt camlocs, adjusted the bottom cowl camlocs for flush fit. The gap between the top and bottom is because the bottom cowl bows outward, when force flush, the top and bottom seems to fit well enough.
Because of the bow of the bottom cowl, it seems that after the camloc tabs are riveted to the lower cowl, getting the top cowl to fit over the lower cowl once the camlocs are installed is going to be a challenge....
I am considering riveting the tabs on the top cowl instead, but I don't know if that is going to make a significant difference. I have installed/removed the top cowl enough times now to know that once the prop is installed, this is also going to be a bit of a challenge as the camlocs seem to want to hang on the receptacles in the tabs.