Aero Original Hercules sizing

[Highwayman64]

I’m saving up to buy an aero original Hercules in either a brown or cordovan cxl horsehide. Do I size down in these? I have a 42” chest and a 30” waist. I often times have to size up to fit my chest and shoulders and then the middle ends up wide. I’m looking for a trim fit that will still allow layers