The left bracket is a little tricky. Here you may want to start with the 180 degree flip over bend. Put a piece of shim stock (body sheet metal) in the middle and hammer it over tight and flat to get the space right. Drill this hole after forming. You might want to keep the shim inside to hold the space during drilling, to minimize any burrs inside the gap. The curl on this part serves to reinforce the thin dash brace after you will drill a hole in it (during installation). If you find the curl too hard to form, you could make this a simple "L" bracket without the curl, and install a long flat strip on top of the dash brace as a stiffener to carry the load.