Injectors, pump, ecu and tune.Pump, ecu and tune you'd be doing anyway. This leaves you space to move later on. Will idle and drive well. No brainier really.
Although not micko's car but tuned by the same guy, mine according to the AFR gauge is 14.4-15.3:1 on cruise. (That's petrol AFR numbers obviously as the AFR meter doesn't know what fuel is in the tank). I can't see micks being any different.What I have noticed was when it dips leaner than 17.5 it gets quite sluggish.. (There was just one cell which needed a touch up. Sorted now)
.... And been in the car for 8 years. Pitty I won't/ ain't push harder with the car ( due to turbo size). It would be good to see where it calls enough after almost a decade of being in the car!
There was a reason why I suggested what I suggested. The ID's will drive a lot nicer than the "older" Sard/Denso injectors. ID's are cheap enough now, it shouldn't even be a factor.
What's your time worth?
Just buy a series 2 and be done with it. Realistically, if you can't afford afford the difference between series 1 or 2 now, you shouldn't buy one. That cost will be a drop in the ocean if you can on keeping it and modifying it.
Leave the standard temp thermo in. Why run an engine cooler than what it was designed for? If its for an overheating problem, sort out your cooling, don't "band aid" the issue.