Selecting a new drive train for my 65

[Dopie]

Folks,
My 65 289 engine is getting a little long in the tooth, so I think its time to upgrade to a roller engine and 4 speed auto. This is not a race car, but would like to build about 250-280 hp.
My thoughts are that going to an injected engine is too much work and cost, so I think I would like use a 5.0 engine with mated transmission, however remove the injection and replace with carburation.

Will my 289, small cavity, heads bolt on to a 5.0 injected engine? Does this make sense or should I use other heads? Again my objective is to not get involved with computers and fuel lines.

Transmission? I obviously need to stay away from electronic transmissions.

I am targeting a 87 5.0 with automatic transmission (overdrive ?), because I think it's carburated and utilizes a manual transmission. Any help would be greatly appreciated. Do you have any combinations in mind that I should consider?

thanks

Dopie