Spares, uneven cook due to tapered cuts. Hot to fix

I am trying to figure out this issue with spares that I continue to have.  Spares are tapered in two dimensions so one end gets done faster than the other.  I really want to find a way to do them uniformly.  About all I can come up with is trying to block some heat somehow but too much covering could really cause flavor issues.  I guess I could cut them in half but I like to run the entire cut and have never cut down any cut of meat for smoking.