Then go for the smaller cam. I recomended the larger one because of the 4spd manual trans. There is a ever so slight drop at the lowest point with the larger cam that IMO the 4spd. manual will cut across. The rpm range of the larger cam starts slighty higher than the off idle of the smaller cam.
This is from a 4spd. owner of 20 years. I have had the Crane cam I listed above in a '73, 4spd Cuda that was then powered by a 318. I just installed the same cam again in a auto (904) trans duster with a 318.