Yep, there's folks on
www.gearhead-EFI.com that do. Dave w (Old School EFI) for one. He'll have you data log, tune, data log, rinse and repeat.
Let's ensure your sensors, ignition, and fuel delivery are all good 1st. No amount of tuning will mask an inherent mechanical issue.
Let me guess, you read Brian Harris' recommended 350 TBI mods and built yours accordingly? Don't get me wrong, he had some good input but there are other ways, and maybe better, options. So, what cam, fuel pump, distributor, and IAC do you have? Did you go with quality parts or buy cheap replacements?
Do you have a fuel pressure gauge or are you going by the "advertised" 18 LB spring (probably from SPR Performance when you bought the 46mm TB from them)? Can you check fuel pressure while under load? A WBO2 is IMHO crucial for tuning "performance" systems.
Why do you have your base timing set at 2° when TBIchips should have set SA tables in his calibration? BTW, FWIU Harris retired a couple years ago, due to health issues, and someone else is running TBIchips.com
As I said, data logging is a great plan
Don't get me wrong, I've been there, done that, never could get mine running right until I explored other avenues. At least you hopefully have the faster (8192 baud as apposed to 160) '7427 which has expanded tables for better performance. My 7747 just couldn't keep up.
At least it was a helluvan education for me, still learning every day
HTH