Well since 1227727 is underhood model of 1227730 and 1227730 was already used for TBI, and chips will run the same in both, and we have TBI wiring diagrams for it :
http://www.gearhead-efi.com/Fuel-Inj...CM-information

I think it may be easier than you think? But I am not sure what mask the 7739 TBI uses?

Also a 1227727 system either underdash or underhood would be not only great for marine but also great for Off Roaders who just want TBI!

EDIT: Ha! was posting same time as Six Shooter...