I cleaned up the A-602-1 backplate, S-602B doubler and the S-603 front plate and shot primer on all. After the primer dried, I got out the squeezer—my most favorite tool of all. I clecoed the doubler to the backplate and squeezed in 22 AN470AD4-5 rivets. Then put the parts back my “finish kit” box—not much in there now. Ok, now that I’ve had my aluminum cutting, drilling, riveting therapy, I can get back to the firewall stuff.