bought a 1982 marquis cuddy.. it has 120 hp mercruiser gm im trying to figure out what type of out drive it has...im buying 1983 four winns cuddy...with a 305 merc..is the outdrive unit transferable..from the 120 hp 2.5 to the 305...new to all this ..the four winns boat 305 is shot ...am i able to swap the 2.5 to the four winns ...plzz. help and advice..marquis boat was free... the four winns im getting for 500... its always been garaged kept and its very very nice shape