I had to go with the larger size suggested. The smaller one was making my car stall on cold starts. Between shifts the RPM dropped too fast causing a little strain on the tranny. It would drop then have to climb again to reach the correct RPM.
Tony
1998 SVT Contour (B/MB) #542 3L
1998 SVT Contour (SF/MB) #1266 parts car
2000 SVT Contour (SF/MB) #1533 3L swap to begin!