I'm not sure I've gotten the start tables perfect but I did at least determine without a doubt what had me chasing my tail on this one.

The "Prime Pulse Width vs. Coolant Temp" table, along with most of the others in this category are stored as 8 bit cells which are then scaled by the mask by multiplying with a floating point constant to come up with pulsewidth. For this particular table that value is 1.5625. This leaves a fairly limited range of low pulwidth values for tuning to large injectors (minimum of 1.56, and multiples thereof - 3.13, 4.69, etc). What I was doing wrong was blindly scaling the table in TunerPro, saving the table and then saving the bin and flashing. My dumb *$$ finally caught on when I was working on hot starts last night and had added 10% to the rows between 68 and 128 ect, and eehack couldn't find any differences to write. The changed cells were getting pumped back through the conversion formula and resolution was being lost. <planting forehead firmly in palm> I suppose this begs the question - is there a way to view / edit the raw hex data in TunerPro?

So assuming I won't be able to get warm starts (around 60c) perfect, I'm weeding through the disassembly to see if I can change the floating point scalar constant used in the conversion formula. Cutting it in half should give me ample resolution to fine-tune this one table.