Not sure just how much clearance that you will have, but it's usually the TFI equipped EFI engine distributors that have the clearance issue with Explorer serp setups.
The Explorer didn't use a distributor, so there was no TFI module sticking out to worry about.
And notching the aluminum bracket does not cause any problems that I remember hearing about. Lots of us have done it when needed and not had any issues.
That said, a couple of the distributor's like broncnaz mentioned would be the Mallory E-Fire and Max-Fire distributors. They still use a vacuum signal, but you simply plug the hose into a port on the bottom of the distributor that feeds a MAP sensor inside. It's all computer controlled from inside the distributor body. Very clean and cool.
Paul