I had to spread the tabs apart on the stem to put the stabilizer end into them. Also had to drill out the holes in the stem tabs bigger to get the bolt from the stabilizer to go through. Hope this is what you was talking about.
Either way works. With the tabs, you just don't have to worry about it slipping and putting your stem in a bind during a race. Had that to happen with my 250R. My tabs have held up so far, just hope they don't break.