Trying to reduce a arc with lighting bolts on each end.

moroderix,

I believe it may be worth trying a simple adjustment by just removing the hopefully circular superfluous top part and rotating the right and left parts of the black/green band behind the 30 YEAR ANNIVERSARY in place and rejoining them.

This based on the centre of the black/green circle(s), after locking the 30 YEAR ANNIVERSARY and everything within the black/green circle, and with Smart Guides being your friends:

1) Select the black or green circle and hope to see the centre straight away, or when ticking the Show Center button in the Attributes palette;

2) With the Line Segment Tool, snap and ShiftClickDrag vertically upwards from the centre to somewhere above the design, then lock it; this is your vertical guide line;

3) With the Line Segment Tool, snap and ClickDrag from the centre to the lower point of the bolt to the right (where the arrow starts), then from the centre to the lower point of the bolt to the right (where the arrow starts); this is your lower right guide line;

4) Repeat 3), only from the centre to the upper point of the bolt to the right (where the arrowhead ends); this is your upper right guide line;

4) Select the lower right guide line, then switch to the Rotation Tool and Click the centre, then hold Alt/Option and ClickDrag a copy of the line to snap to the upper right guide line, then delete the copy of the line; this gives the rotation angle;

5) Select the vertical guide line from 2), then copy it twice in front of itself;

6) With the top copy from 5) still selected, switch to the Rotation Tool and hold Alt/Option and Click the centre, then Click OK to rotate this part into place to the left;

7) Click the other copy from 5), switch to the Rotation Tool and hold Alt/Option and Click the centre, then deselect the angle and add a minus in front of it, then Click OK to rotate this part into place to the right;

Now you have the cutting guide lines for the black/green band behind the 30 YEAR ANNIVERSARY;

😎 Select the black/green band behind the 30 YEAR ANNIVERSARY, or (each of) its constituent parts, then cut it at the cutting guide lines with the Scissors Tool, snapping to these, then delete the top part;

9) Hide the cutting guide lines;

10) ‌‌Select the leftmost part of the black/green band, then switch to the Rotation Tool and hold Alt/Option and Click the centre, then Click OK to rotate this part into place;

11) Select the rightmost part of the black/green band, then switch to the Rotation Tool and hold Alt/Option and Click the centre, then remove the minus in front of the angle, then Click OK to rotate this part into place;

Now you ought to have both parts rotated together;

12) Deselect, then ClickDrag with the Direct Select Tool over each set of hopefully coinciding cut points at the top (if not coinciding, Object>Path>Average Both may be used first) and Join them; if there are more paths on either side rather than one path with a green fill and a black stroke, lock the other set.

This ought to give a simple adjustment by just removing the hopefully circular superfluous top part, rather than having to change the shapes of the bolt parts.