OK, so basically here's a HD run through what i've got: I like the Cobra bracket I have for 2 reasons - they raise me just enough to not be uncomfortable, and also all the holes in them are already threaded. So good security there. Combined with the seat already having threaded holes in the bottom, I fortunately don't need any captive nuts etc. Here's a pic of what the Cobra bases look like - they go horizontally, much like SteveBs race car pics. http://i41.tinypic.com/xqgc9g.jpg I've got to sit fairly far back and low down due to my height/length, so I end up nowhere near the bolt holes. Here's my high tech paint.net drawing of what I need - hopefully this clears up the dimensions a bit more. Click for full size: http://imageupload.org/thumb/thumb_208864.png http://i40.tinypic.com/20jbe9.png Hope this helps!