Early muffler nuts, castellated or not?

I picked op this earlier muffler for my 14. I think since it would’ve been a January car this muffler might be correct? I have the later cast end muffler with integral mounting brackets now. I know the change was made sometime during the 14 model year.
Should these nuts be pinned or were they just hex nuts originally? I bought the bolts for my other from a vendor and there were regular nuts and lock washers with the bolts.

Original nuts are plain and no lock washers were used. The whole thing gets pretty rusty which I suppose helps to hold it together. Personally I drill them for cotter pins.

Ok. Thanks Royce.

More here:

I have two 1913’s and they are similar. I’ve had some difficulty finding the correct bolts for them. I see no need to go to the trouble Royce has done. Why? Because the bolts get rusty fairly quick, and that holds the nuts in place just fine. I’ve put many thousands of miles with no issues. An interesting side note is the mounting bolts for the muffler to the frame. They used a standard Ford bolt, drilled for a cotter pin, but did not use a castle nut on these, only a plain nut, and then a cotter pin.

Of course you are right Larry - I just did it to make it look like it did originally.