If the P51 stays fast and resists the urge to slow down and get tight with the F4U-1A, there isn't much the F4U can do to force the issue, IMO. In the fights I've had against the better P51 pilots, I find that in the F4U I'm just defensively dodging slash attack after slash attack, until I can convince him to turn a little too hard or enter a rolling scissors with me.
Long-term, it ends up bleeding my E down to a point where dodging is difficult, although honestly it often seems to just be a wash. I can dodge all day, but I can't force an attack myself. If I can use a Barrel Roll Defense and hit him as he passes, I can normally force the issue enough that he'll turn with me, or leave me alone to lick his wounds. If that happens the fight is over either way...
The issue for me is that since I know I can turn better (in the F4U), I'm willing to give up a bit of E for a quick shot. If I do that and miss, and the P51 fights conservatively, I can no longer press an attack (since I'm not as fast as him). Knowing that, I'll often be very E-conservative against an equal or higher-E P51. One "trick" that works for me is to give the P51 an advantage on the merge, hoping to "bait" him into pulling hard for an "easy" kill. I'm basically trying to look like I don't know how to set up a merge, or am willing to accept a poor position. Ideally, he pulls hard for a position on my six- which I can then turn into an overshoot, which puts me behind a slow P51...