Nick got back to me and advised the pump will bolt up. BUT..... After more thought I am going to wait for the correct NOS to show it's rare head sometime in the future. I could not get my brain wrapped around why there would be a different part number if it would work. I keep going back to flow rates. When I look at the 95 service manual, it shows different flow rates for each model's pump. As Nick also agreed, there is a difference in fuel consumption so makes sense would need different outputs to get ratio correct. Looking at the 94 GTX, the engine is not an x motor. When I look up the specs, the 94 burned about a gallon an hour less than the 95 657x. Although the pump may fit, looks like it would cause me to run lean. Guess I will be staying premix!