Dont't forget about the thick sheeting for the fuse top. I have an OS 70 FS inverted on mine with the mount sticking a little above the firewall thinking I would have to shave it down. Last night I sheeted the top and to my surprise I will not have to trim a thing.
Also I suggest Fiberglass Specailties for the cowl, looks really good. I will still make the ABS cowl as a template only.
Good luck