Jerry, over here Landrover had a similar thing. The electrically operated injectors on the TD5 direct injection diesel are inside the rocker cover, and on early vehicles the loom wasn't sealed properly.
The result was that engine oil ran through the loom back to the ECU under the driver's seat, and filled the area under the driver's seat with oil. Result, apart from a mess, was poor starting, misfiring and loss of power. Remedy was a new front loom at £800!
To your original question, that sort of thing is done quite commonly for motorsport and fast road cars, so no reason it can't be used. We have a GM engine over here called the C20XE, a 2 litre 16 valve 4. It's used in all sorts of performance engine conversions, not only in GM stuff, and it's common to remove the injection system and fit carbs.
Replacing the ignition with distributor is less common, and I'd have thought it's something there'd be less good reason to do.
The only thing I wonder is whether with some engines going back to the past on induction and ignition would result in a significant loss of power / efficiency.
