1989 18' with an 1988 Merc 115?

[gman1001]

Hi all, I've searched and read all the comments here about 18's. Great info and insight.
I've got my eyes on a little fresh water gem. it has the original 1988 115 merc. Can anyone tell me what I can expect from the ride this boat will give me with this motor?

Of course a 150 is probably the power I'm looking for. Will this boat be a dog with 2 people in the boat? Any other insight or thoughts would be great. Repowering right now is not an option.

Also, seems like the only real complaint about the 18s is the low transom for the motor cutout. I see somefolks have 'blocked' in that area. Anyone know of an aftermarket solution for this blockout? Just curious.