Interesting project. Model T coupe kit with 2.3 lima (112hp, 135tq) and a T5 transmission. Or you could do the Model T pickup kit and use the 2.5 lima that came in later Ford Rangers (117hp, 149tq). Of course either engine could go in either body, but the 2.5 is more of a tq engine and the 2.3 is more of a revver.
I figure that either configuration would yield 30+ mpg and a 0-60 time of 5 seconds or so – both stats dependent on rear end gearing.