This is going to be OOB, other than a little extra work around the engine details and pit...no aftermarket.
I am still not a fan of Trumpeter...weird mold seams, enough detail for a "start" but they seam to stop short...and accuracy issues all over the place. Regardless...it'll look like a P-51D when it's done!
Starting in the pit, wires added to the gear behind the seat, seat back (yellow) added, belts are tape (rather than the included PE). The I.P. needed some help as well. Some of the holes for the instruments needed to be drilled out, as they were stupidly small. I used acetate instruments from the scrap box.
The "tunnel" behind the radiator needed to be scratched. the kit parts fit was awful...gaps down the sides and about a 1/8th" gap and step at the rear of it...stupid!
New side walls with sheet styrene, along with a runner to stop the "roof" piece when it goes in later.
The engine isn't terrible...but NEEDS a lot. Aside from the wires/plumbing you can see...this is all they give you. An incorrect oil tank, basic engine, and engine mounts. No framework for the cowling panels.
Scratched up the framework...
...and that's where she sit right now.