If you're thinking of doing Happy Jack's Go Buggy those decals are completely wrong - that's the incorrect warbird. When he was flying the airplane in its original finless state. it had the earlier 20th FG nose markings, not the "keyboard", and the codes were MC-O

Photo attached of the airplane in the correct markings. Only people who ever did this right was Meteor/Cutting Edge. Dave may still have 1/72 decals of the sheet in stock.

Fiebelkorn's markings are correct, and since the Arifix kit is finned, that's the one you want.

1 attached image. Click to enlarge.

Thank you both for your kind comments. Kit worlds decals are subject. Happy Jack's Go Buggy is a good subject but, its been done. I've been looking at photos of other aircraft and will be using some but, not all of the decals provide on the sheet. Not all of the 79th Mustangs had white capped spinners some of them were in natural metal with back half painted in black , some earlier P-51 B/C where painted in solid black. The anti-glare panels on many of the aircraft were painted up in Olive Drab. The white and black bar pattern on the nose of the aircraft didn't always have white paint they were left in natural metal. Kit world would have you paint the anti-glare panel in black. For the Airfix kit the D model I will be doing P-51D 44-51198 MC-L "E.K. and Jay Bee/Suzanne". The Arma kit I'm toying with the idea of either doing a War Weary machine or using the Malcom hood with a machine that had a tail fillet installed on a B/C model. I've been looking at some gaming skins too for cross referencing. Some of the artists do some reasonable research.

Looking forward to these Mustangs as well, Stephen @stephen-w-towle
Happy New Year.

Yeah, along time ago I got tired of doing box top models. Which are still a good thing but, they focus on the aces or folks who did something extraordinary who posed in front of "their" aircraft for the press. Everything is righty, tighty, neat and clean. War weary planes have story to tell. While doing some research, I came across some photos of A-10s flown in the middle east showing the noses of several aircraft that had dings, bumps and bruises from being hit by the booms of tankers repeatly. Something you normally don't see on the net or in press releases or from photos taken at airshows. War time conditions, the reality for pilots and crews who flew the aircraft. Which where used and abused and did/do what they were designed for. Bring on interesting markings, paint schemes and weathering.

Ok where winging it. Two apples and oranges builds. The Airfix wing is on the top and to add a little interest I'm filling in the engraved panel lines.

1 attached image. Click to enlarge.

A shot of the fuselages. Again more decals, I've spent about six or seven hours doing little tiny decals. The Airfix kit has one decal for the instruments. I managed to break the control stick and shoot the Quickboost seat into oblivion. Spent 4 hours on the floor with a flash light praying to the model gods and using color commentary. The Airfix is on hold until a new seat gets sourced.

1 attached image. Click to enlarge.

Progressing nicely, Stephen @stephen-w-towle, except for losing the seat.
Let's hope you find it, or a replacement, soon.
These dimensions for decals are definitely not easy to handle but the result looks great.