I have very few photos of 4201, most I have found are of 4204 and 4205.
And of course, the size of the number varies as well...I would have thought the side numbers were a standard size, except perhaps on the last repaints.
I can see that 4205 has its number above the rear door, with 42 on the left side and 05 on the right side. I can't find any other photos online of the rear of 42 class...so did any other of the class have their number at the back and if so, was it split like 4205 or not?
I have several photos of 4204 in IRA where the side numbers are almost 50% larger than other locos...but most of the photos I have found on the internet show the 42s with no side numbers...but I am only looking at IR and IRA...Yes, I think 4204 in "austerity" had larger, thicker numbers than standard.
Variations to rear decoration of 42 class includedat least six decoration variations for 42 class