Not all Titches I've seen have that 1930s look, but that one certainly does with the high turtledeck, what must be a side-hinged canopy, and gear fairings that are suggestive of full "trousers." I suspect that builder was going for a Percival Mew Gull look, also a classic from the period and a style i love for a single-seater.
That certainly sounds right to me. These are beautiful renderings of some charming aircraft, but it puts my teeth on edge when I see the relatively low aspect ratios and taper ratios. With such a shallow taper, you get relatively little of the benefit, but all the aggravation of making tapered wing spars and different-sized ribs for every station....a modernized Sparrowhawk type homebuilt should by all rights have a significantly narrower wing chord...
Seems that I have heard that someone is building carbon wings to replace 13.5 percent thick short span rectangular wings in sport class. Perhaps that same someone could find a sponsor / unlimited owner who would be willing to fund a carbon wing for a P-51.If there were some sort of magic saw that would reduce wing chord without disrupting the wing profile, the Unlimited guys would be all over it.