Not too difficult to make base map:
1. set VE=1 across entire map
2. use wideband O2 system with on-board datalogging to record AFR
3. do runs to redline at various throttle-openings, 10%, 25%, 40%, etc.
4. download data and draw pretty graphs for analysis
5. update map to adjust AFR based upon datalogged data
I really like this all-digital unit from TechEdge.au
WBo2 2Y DIY Wideband Unit
Can datalog RPM, speed, TPS, AFR, even EGT if you want.