lower gear box

[cooter dog]

lower gear box

hello all  .I replaced the water pump on my older 40 horse mercury classic . i watch some videos on this but now i having troubles getting the shifter in the right position had it working backwards drive was reverse ,and reverse was drive.Its looks so easy not sure what i am doing wrong .the videos show line them up in reverse the prop should turn counter clockwise i think i try putting this together about 10 times any help would be great thanks for your help