I have an intake manifold modded to accept a 65mm mustang throttlebody along with a mustang TB modified to work with the capri throttle linkage
its like a 3" inlet, you'll need to get a little creative with pipe, it just barely clears the valvecover but some grinding an a silicone adapter will make it work
So you're going from a 52mm TB (2inch) to a 65mm tb (2.5) I've run some math and it its got 30% larger cross sectional area which is going to mean a berzerk increase in flow
Let me know if you're interested in it