1980 Mercruiser 260 exhaust elbow/manifold gasker question...

[CanyonDoug]

1980 Hammond... like the original Challenger... anyway, has always had a hot spot on the starboard side... looks to be original exhaust log. One on port side seems slightly different. JUST unpickled from sitting out the winter... (finally). replaced water pump last year, thermostat, impeller/pump kit in drive.. Anyway, sitting at idle it slowly started creeping up past 160(while on trailer with hose hooked up)... at idle. Gave it some gas and it just got hotter. Had a infrared on it last year to test temps, and stbd side was hotter with a hot spot around the third cylinder back... Figure it's time for fresh manifolds, even though only a fresh water boat from what I gather. When I pulled the elbow off to take a peek, I noticed the gasket had not vent holes to line up with the water vents. Upon reading i find these are referred to as dry joints. Not sure if this boat is supposed to have them... Engine serial # 5425711... outdrive # 5622772. Just ordered fresh manifolds from Amazon, sierra 18-1950 & 51.... But I am perplexed about the restricter style "dry joint" gasket used... looking online at boatinfo.net at the manual, and it does not show that for the 260. I have no riser installed. Guess dry would be preferable, but wondering if this lends to the hotter running condition (Although it seemed to run OK at around 165ish or so after new water pump... but manifolds always very hot to the touch, particularly stbd.

Question is.... go back with a restrictor type gasket, or no? If so, anyone know the part number and who makes it... Sierra...? Thanks a ton for any help.

[powerabout]

show us a photo of the engine so we know which cooling system it has