mercury cylinder head casting # 18419-C1 ?

[snickers]

My motor is a mercury 150 V6 XR1/EFI (2.5L)
1995-94? Serial#: 0G017594/block #: 884-9763CA
damaged head cast#:18488-C4(vs C1 can't tell)
# on end of head : 7/3/93
# inside of head: 3E02E C
I bought the head #18419-C1 thinking it was the same as my damaged one. Visually, it seems identical except for it did not have the dowel hole on each end. Upon arrival, the outside diameter across each cylinder is 3/16" narrower, and the width (across the long sides)is slightly narrower. What application and year models is this head used on? From different block type?
Also please verify my motor's year, model and application.

thanks for help....Snickers

PS: I have several mercury lower units I need to identify model year and application. Here's the numbers: 1647-6049
1647-9147C
1655-7332

[boats.net]

That serial number uses head number.
18488F 1 HEAD, Cylinder (Casting #18488C4) (150/175)

[boats.net]

I didn't find any of the lower unit part numbers you listed in book.