If possible – measure it close to the K-frame bushing area – to get an accurate reading.
My police (’84 Gran Fury) bar is not a uniform thickness throughout the bar.
I measured all 3 of my bars before (’77 wagon, ’86 5th Ave and the one above) and wrote down the details – for future reference.
Well guess what is missing – my numbers.
I have no additional or helpful information to give.
BudW