You don't have to 'RUN' antifreeze through it, you can simply drain, poke the holes in the block and exhaust manifold, disconnect the bottom end of the hose from the circulating pump to the thermostat housing, disconnect the raw water intake hose at the impeller housing, point it down in the bilge to drain. Then if you want to use NON TOX ONLY antifreeze you can:
reconnect the bottom end of the big hose that goes from the circulating pump to the thermostat housing, and disconnect the top end. Now put a funnel in the top end of that hose and fill the engine with AF till a bit comes out the thermostat neck, and reconnect the hose. Now your engine is full of AF like you wanted it to be. Next, disconnect the hose feeding the exhaust manifold and fill it with AF till a bit comes out the exhaust housing on the transom mount, reconnect the hose. Now I don't know if the Volvo SX used a
drain plug on the port side of the pivot housing like the OMC Cobra, some did if so I'd remove that, poke the hole, put the drive down, to make sure all the water left in the raw water intake system drains.
On my boat when I winterize it I do all of the above, and then fill the raw intake hose with AF till it runs out the outdrive water intakes.
Doing it this way I have never had a freeze up.
Keep in mind that adding AF is only necessary to reduce corrosion, to prevent freeze damage you drain, first last and always.
Running AF through is risky and wasteful. Either drain and leave it dry or back fill with AF as I described. I use only -100 or I mix up a 50/50 mix of Sierra no tox AF. I feel that the -50 or -60 get hard at 5 and 10 degrees above zero (but do not expand) but that is not the best thing to use in a cast iron engine.
my experience based on 20 years of winterizing raw water cooled engines.