It's really a non-issue. Yes, you might end up with a quart or less left in the system after a change, but you've then changed out 5 quarts worth, roughly 83%.
If you want to drain it all, just remove the two fittings from the sandwich plate and flush the cooler using compressed air. I plan on doing this every 3 changes or so, which should be about once a year.
Even with the fittings at the bottom you will still end up with oil left in the system, just not as much.
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2009 NISMO # 0193 | QAB | Albums! | 05.04.10 (Dynojet) 291.94hp/248.28tq
Oil Cooler (DIY) | Custom Headlights | GTSPEC Braces | F.I. Long Tube Headers
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