swapping out a Autolite 2100 2bbl

I have a Autolite 2100 2 bbl carb in my 68 Mustang, which keeps givng me problems. Short of rebuilding the carb, my mechanic recommended a Sniper EFI 2 bbl.

I browsed the Holley site but I am not sure which one would be the best fit. Your expertise is needed.

Thank you for your assistance.

Jim