I've spent a couple of my modelling sessions pouring over the few photos of Centauras engined Firebrands that appear to be available in an effort to work out the lettering style used on the underside of the wings. The problem is I'm modelling a 1947 scheme so basically it's still WWII, but the Firebrand soon appeared in Pattern 1 (low on the fuselage delineation between EDSG and Sky) and Pattern 2 (high delineation) it means the majority of the photos show Post War lettering. The trouble was caused by photos showing the K in EK632 seeming to be in the Post War font - probably just a variation, but I needed to check what the numbers looked like, the squarer WWI style or the rounded Post-War style. The Aircraft in detail used Post War font in the plan views and had the code on one wing back to front so I wasn't trusting it. In the end I found a photo that showed a parked Firebrand with a bit of number visible on the undercarriage door - WWII. I could then print these up.
As to the white letters and numerals on the fuselage, the small 4" white codes and titles came from a ModelArt Gen005 sheet. The larger C from a Hannants sheet of WWII letters, but no one did the larger chunky 100 numerals in the correct size in white. I tried cutting templates but this was a fail and so I printed the outlines faintly onto white decal paper and cut them out. The ink was unsealed so washed off. Despite doing a few extras and taking my time it's impossible to do a neat and consistent job at this scale, therefore what you see below are not only the best side but have been touched up with some white paint.
Guns and spinner were added, and then a I drilled out a hole for an acrylic rod, like the rest of the build done after everything it should have been done before.