Having an MS3 with the complete IAT correction curve, and an insulated/isolated IAT sensor, I started to believe the hot restart lean condition was not related to the Gair, but rather was a heatsoak issue with fuel. now from the factory certain year cars came with what is known as a PRC solenoid (yes, even in the US) this solenoid was installed such that on hot restart it blocked the vacuum signal to the pressure regulator, keeping the regulator from pulling fuel pressure.

so I thought, why not just use mazda's own design. Having left my PRC solenoid intact and stock I simply connected my harness pin for the PRC solenoid to the MS3Xs VVT output in my adapter harness, you could use any of the driver outputs capable of that current though. I just dont have VVT.

then I programmed an on/off output condition to the VVT output with the conditions of coolant >160 degrees and <150 seconds

so now when the ignition is turned on, if coolant is above 160 then it will activate the PRC solenoid for the first 2.5 min preventing the regulator from pulling fuel. so far this has worked great.

I also dialed in my EGO correction enough that it runs on idle as well to keep things in check. haven't tried this without the EGO so I don't know if it is 100% necessary but every little bit helps get things just right.