The plans don't warn you about this, and maybe I'm just stupid, but if you just clecoe up the roll bar, match drill and rivet, it absolutely, positively will not fit your fuselage and cannot be 'stretched' or 'shrunk' to fit after the fact.OK, I'm stupid.... I figured it would be perfectly pre-punched (though not to final size) and would fit flawlessly like everything else. Nay, nay fool !
The problem is that clecoes are slightly smaller than the holes they fill, and thus allow minor relative adjustment of the parts being joined. In the case of the roll bar, this adjustment at the apex, or top center, affects the distance or spread between the legs at the bottom by as much as 3/8 inch, reducing your chance of getting it right to..... zero.
The solution is to only use a few clecoes at the apex, allowing you to 'fit' the bar to the base mounts. Then measure the spread exactly and create a spacer to use as a jig. Add more clecoes, remove from the bases and match drill using the spacer between the feet.
Now I'm smart! Fits like a glove.
Dick
