I had heard that this bracket to the firewall has caused some builders to have problems with rivet edge spacing in the past. I noticed that the other side (not shown below) was better and I figured that was because I had insatlled a 10-32 bolt in the bracket while assembling the firewall. This side (right) had much worse spacing. I cut a heavy piece of steel and drilled the whole out for a 5/16" bolt and torqued it down. The result was amazing. I am very happy with the results.
very poor edge spacing
used to pull bracket tight to firewall
pulled the bracket in nicely (blue mark to blue mark)