i've just purchased a nissan 40C 2 stroke, blue, so its a pre 90's model. i'm going thru and getting it ready to use, but wanted to change the impeller on it. i've removed the 6 bolts that hold the lower unit on, but it drops about an inch and half and stops. the linkage is holding it on, but i see no location to disconnect it. i've done this on OMC, but nissan is new to me. can someone let me know where to look to allow the linkage to disconnect and drop the lower unit? thanks