I didn't like the FBO plate. It's not accurate. I had to use the smallest slot (10 degrees) and was still getting 16 degrees mechanical. That's just too big an error margin. I pulled it back out, remover the distributor governor and welded the slots and filed them down to get only 10 degrees mechanical. So now I'm at like 20.5 initial and 30.5 mechanical. Slant sixes don't like much more than about 30 total. Yall need to check these plates with a GOOD digital light though, to make SURE you're getting what the plate says, because I was not.