Might, but the pressure drop across an "orfice" vs a length of tubing is not the same thing. I have been retired for 11 years now (somethings one forgets) but I think I remember a thing referred to as the "Reynolds Number" that deals with turbulent and laminar flows and the like. Shows a graph that deals with all the physics of an installation.
For a comparison, what are the sizes of the jets in your Force 150? I'd bet the total area of them is less than 1/4 inch, way less. So in short, I'd do it and not look back. Besides I'm going to bet the suction pressure (vacuum) your carb's venturis is way less than the suction pressure of your fuel pump even though it has to suck on a long hose. Besides, the 3/8 size fuel line is more appropriate and is used on the Mercury 150 engines....at least it was on my son's and that reduction in pressure drop will/should way more than compensate for the reduced fitting size.
Mark
