API Clamps for Camper Shells

http://apiclamps.com/ac110f.html
http://cgi.ebay.com/ebaymotors/API-Truck-Cap-Camper-Shell-Canopy-Toyota-Tacoma-Clamps-/250682146738



I'm looking at these clamps for securing a camper shell and possibly some other bed ideas, like a DIY canoe rack.
I assume others have used these... Can anyone tell me which of the three sizes is the best for our use? I'm guessing the medium (7/8") is the one.
Anyone know offhand if these are available at any retail outlets in Canada?
And does anyone know if regular C Clamps will work on our rails?
BTW I'm a 2010 Access cab

Thanks in advance for any advice

 

C clamps will not work. I have a Hawk Cap made by Paris Caps in Brantford ON. www.hawkcaps.com I am not sure they are still in business. They have special aluminum clamps made for Tacomas. Should be available at http://www.vanandtruckworld.com/. I saw a location in NL St John's last time I was there.

You can see the clamps on the bed rack build thread

 

I have something that looks very similar for my topper clamps. The one part of it doesnt go into the rail like this, but the rest looks the same and they work GREAT!!! Definately worth the money.

 

Bumping an old one for anbody w/experience. Who has these?

 

Bump again to see if anyone has used these, including previous posters. I'm talking to a guy on Craigslist about buying his Leer shell, and these clamps look pretty easy to use.

 

I have them on my ARE MX shell. They are easy to install in the deck rail,and easy to tighten and remove. So far shell has held well even in 4x4 rocky country .

Az