You can do the same thing on a 4-108 or at least you can on mine! There is also an old sump entry where once upon a time my engine
had a built in pump although it is long gone and capped. I prefer to change through the dipstick. There are a few different models of 4-108 so I suggest you wait until you get there and hopefully the boat will have an owners manual. If you have some pics and want to put them up I'm sure someone on here can help you identify which 4-108 it is. I think it is about 5 qts, could be a bit more ( I always have to look this up in the manual). We use a Fram oil filter
, PH2821A. Bought it at Advance Auto parts
online but if you are in a rural area (used on tractor engines) they may have it in store.