restricter riser gaskets

[Northern Eclipse]

I have just replaced my riser gaskets on a merc 350 magnum with 4" inch centre rise manifolds and thru-transom exhaust (no 'y' pipe), my question is this, the new gaskets that I got from a merc dealer have the water passages open on all four side's, but the old gaskets were a restricter gasket with only 2 sides fully open and the remaining 2 sides closed with just a small 1/8inch dia. hole...does it make a differance which gaskets I use? just a bit of info,motor is raw water cooled and my merc manual does not clearly state which type of gasket to use.

 

[a.d.mobile]

Re: restricter riser gaskets

the small hole is in the stainless plate correct? if so should be no big deal as long as the other openings dont get blocked off.