screw

Could you give me recommendations on the best way to attach interior panels without having screw heads exposed (roof panel, a pillars and door side panels)?

in the photo i have a radiator exactly like this one . i need to know what the large red screw on the right side is for and the small red screw on the top left and if it matters which side is hot and which is cold on the hoses. thanks tom

Hi all . another Question for you clever people .. I am running a 600 Holley and doing the final settings and I cant for the life of me remember ... is it screw the air screws in to richen the mixture and screw out to weaken ? Thanks guys John..