Stan, you've got it right. Intake air temp, engine temp(coolant or oil) or even just a factory type3 style warmup sensor in the head. O2 controller and wideband Bosch sensor. Batch fire and wasted spark is WAY easier on a type1 and is VERY workable.
All modern EFI systems adjust the fuel pressure with a regulator. It is usually hooked to manifold vacuum. High vacuum(low throttle) lowers the fuel pressure, Low vacuum(wider throttle) increases fuel pressure. The regulator keeps a specific fuel pressure at all times based on vacuum. This will most probably work well for Mike's engine as it doesn't deviate too far from stock with regards to vacuum pulses.
Stan and I are going to have a more difficult time with LARGE valve openings and big valves. At the very least we'll need to tap all 4 intake manifolds and tap them into a large vacuum accumulator. Lenny had the same pulsing vacuum problem on his Raby type4. The solution MAY be to set the regulator pressure and not use a vacuum input, or only give it a narrow range of adjustment.
Proper injector selection is important here to ensure a wide enough pulsewidth range for all running conditions(lean and rich, hot and cold, and load).
Mike, I also thought of using the existing line as a return, and running a new line to feed the fuel rail from the pump. That's easier in a Spyder than a tunnel/pan car.