You have a d16z6 you are starting out with one of the best d sohc motors. Your trans is already geared down compared to the rest of the ds. Don’t worry you can chip the p28 ecu and adjust fuel and timing much like changing jets/power valves in the carb and springs/weights in the distributor. Easy just strokes of a key board.
You need to look into a turbo to push 250hp. You just go big fuel pump bigger injectors and tune. The motor will hold up no mods just make sure you find a good tuner. Or if you do it yourself run about 11-12 af ratios on boost and about 1 to 1.5 degrees retard per psi. You can only push about 9-10 psi before the stock map sensor pegs a 5 volts.
Don’t worry about msd and all that the stock ignition system is good for about 400hp. Just close the gap on your plugs a bit.
I to am a converter I used to run v8s. Hondas are not hard just pick up a book or 2 at your local book store to get the hang of it.
The pgm-fi works like this looks a map (manifold absolute pressure sensor) and engine rpm. If you are running vacuum your throttle is closed. Injects less fuel and adds ignition timing. Much like a carb with less air running threw and vac advance full on. Less vacuum more fuel less advance. Just like a carb with more air and vac advance off. As engine rpm increases more fuel more timing. Not that much different then your mach 1 set up.