As a younger man I used to fish larger lakes with a small downrigger mounted on a 13 foot aluminum canoe..

Also used them from smaller (e.g. 16 foot) class aluminum boats........

Best mounting options depend on the configuration of your boat but my rule of thumb is "go way back" (e.g. keep them near the stern)... For most boats I would be looking at the rear corners. Put a piece of plywood on the corner and mount them so they point backward at a 45 degree angle.......

When two are fishing the guy running the outboard looks forward for traffic and the guy in the front keeps and eye on the riggers....... Not the ideal situation but with small boats you have to make compromises........ but look at the bright side.... You don't need to burn $100 worth of gasoline to bring home $20 worth of salmon..