2 questions. I am planning on putting a 95 5.0L in a 68 Mustang. If I do an electric fuel pump, how does that install in a 68. Also, will Mac shorty headers fit in the 68 engine bay without hitting the shock towers?
Well, I don't know about the headers, but I recently put an electric fuel pump in my 68' Cougar. It's super easy if you have a day to spend on it... The things just bolt to the underside of the car wherever you want to bolt them, the only real tip that's all that important that I can think of is to put the fuel pump as close to the tank as possible. (electric pumps are better at pushing fuel through lines than pulling it). also it may help to use a fuel pressure regulator. I found that my pump was puttng out too much pressure and it was pushing up my carb floats . Use steel fuel line or braided line if you can, and plan it out so you have to use as little line as possible with as few bends as possible too. Hope this helps a bit.
I doubt the headers will fit. Are you going to use the fuel injection setup? If so, there are several companies that sell the electric fuel pump that is specific for that application (high pressure 38+ psi), they also sell a bracket to mount it right by the tank sender outlet. If going with a carb and using a regular electric pump, they usually include a bracket and you can fashion your own to mount it near the tank.
There is plenty of room in the rear beside or above the fuel tank to mount an electric pump. Mount the pump on a sheet metal bracket to lower the pump, mount the bracket as close to the tank as possible, preferrably towards the bottom of the tank.
I don't know about the Mac shorty headers but in my car there is plenty of room for headers, at least 3" between the 289 head and the shock towers, they put 390s in these cars from the factory. My Heddman long tubes have plenty of room.
I found the ideal location for both my 65 and 68. The well that exists on both sides in the trunk area provides a nice flat surface under the car. Just mount the "hoops" and slip the pump in from the bottom. Keep it as low as possible, since they are gravity fed.