I've pasted LA-7s when flying a Mustang D a couple of times. Maybe it was just because the pilot was a rookie, maybe not. Most of the time, those LA-7s guys are packing more speed than they can handle and I can force an overshoot by chopping throttle and popping the combat flap, then taking a shot as the LA-7s goes on by.
If the pilot is perceptive and cuts his throttle, then I keep the throttle back, combat flap down, and go into a hard yo-yo or nose-down turn. Either the LA-7 will go into a lag turn (in which case I'll tighten the turn and get around on him), lose vis on me (in which case I'll be heading away from him and can come back around for an attack), or eventually we'll get slow enough that he has control issues (in which case I'll pop him just before somebody pops me). As soon as I see the LA-7 twitching in a stall, I'll press my attack and spray in his general direction.