I have an A-3 n and it shakes on me in first gear sometimes even though i just put brand new clutches in less than a week ago. check the corners of the clutch where the pins for the springs are in second gear clutch because these use to break(a problem tomos had with A-3's) and the metal corner would go into the tranny and not only make it shift completely different, but chew up the gears. When it happened to my tranny first and second speed gears were stripped and it was 150.00 to replace the two gears, not to menchon all the time it took getting the meal shavings and debris out of the tranny case. Check that and you should be fine. Other than that if the springs are tight just soak the springs in some WD-40 for a while (make sure not to get WD-40 on the clutch part) and reassemble and it should be alright. Well thats my 2 cents. Good luck
Jeff