[Graham Inchley]

Another point worth noting is: When joining two metals of differing specification, as with aluminium sheet onto steel, the rivet spec should be the same (ish) as the softer metal. This is the main reason for rattling rivets, the harder spec of rivet eats into the aluminium over a period of time due to vibration. I have set literally millions of rivets whilst carrying out major airframe repairs around the Globe during my Naval carreer. Cherrymax are the best blind type of rivet, they set flush (no mandrel protruding from rivet head) and have a shear stress not far short of a hiduminium solid. One snag, they are expensive. Grip length is quite critical with these along with accurate rivet clearance (3.25mm for 1/8" and 4.1mm for 5/32").
A good rivet to use is the all aluminium MBC rivet made by Avdel (I think). They have a very forgiving grip length i.e. as long as they are over length they will grip. We used these for battle damage repair because they are fast to install!! One shortfall is that you cannot use a standard type of rivet pliers because they have a special locking collar around the stem. Rivet clearance for these is 3.2 and 4.0 respectively.
Wet assembling is also important as you say Bill. For this application, in my opinion, a polyurethane body sealant is best. A little dab around the rivet is not a bad move in my experience. It helps to prevent the rivet spinning when it all goes horribly wrong and you have to drill the b*gger out!

Popped into Southern GT's yesterday to check out a few bits and pieces with Mick. All is well and looking good.