Noah,
(assuming on the deck, without being able to dive for speed/options).
When fighting Spits, I'm not afraid to drop flaps and try and pull for a quick shot. I'm also not afraid to keep them down and go for it over the course of several seconds, hoping they'll grow indecisive or make a mistake.
The thing you need to watch out for, is being drawn into a lengthy nose to tail chase where the Spits' better turn rate starts to gain an edge. Like Saxman said, you're going to want to revert to nose to nose. This will often briefly expose you to a shot, and you may very well be shot down, but I'd rather take that chance than wait for the inevitable in a nose to tail chase.
Really though, this is reliant on the sixteen's driver not flying very well, and disregarding their upward options. Then again, it's not uncommon to forget that they have another option than a flat turn.