i have used almost evrey type of rivet there is.. from Cherry Locks, to Hucks, to aluminum and steel solid rivets.. i was a sheetmetal man in the military. rivets are good for attaching thin sheets of metal.. for use on a bracket.. dont go with rivets.. use bolts. stronger than rivets and are thicker for a more secure hold... rivets have a tendancy to break when you use a small rivet to hold a thick piece of metal.
These are 3/16" diameter rivets, the metal is thin, 1/8" thick bracket metal and the lip on the radiator. I plan on bolting the brackets to the sheet metal on the front of the car. Still "no"? I have the receipt, and can take it all back...
Already answered the structural question. On the airflow question.....you want the available airflow from the front end of the car to go through the radiator. Not around it. By creating openings around the sides of the radiator you allow the air to flow through the path of least resistance....ie: around the radiator, not through it. Don't use rivets. You'll end up running over your shiny new radiator after it vibrates the rivets out of the mounting brackets.
You can order it from here: http://www.duckproducts.com/products/detail.asp?catid=1&subid=1&plid=569 Fo' real.
Based on your setup, I would say 200 MPH tape would be overkill. Go with the 150 MPH tape and to keep the weight down ... just my 2 cents
Just wondering how it all worked out for you. I installed the same 19x22 Griffin in my Mav last year. I'm running the Flex-a-lite fan and I can barely fit a finger tip between it and my water pump shaft. I cut out just enough of the frame support to achieve that spacing. I'm running the flex-a-lite on the motor side and dual 9 inch fans on the front of the condensor. Temp runs 200 with the AC running in Houston area traffic....in July. Not bad. Good luck with it...