I had unscrewed the filter at first to drain some oil and get an idea of what kind of shape it was in. It looked like it was new when coming out from around the filter, which is why I didn't focus more in it in the beginning.
Turns out the gummed up oil cooler that was completely blocked behind the coolant reservoir, had been gummed up completely before I got to looking at it, so what I originally considered gummed up wasn't even close to how bad it originally must have been.
Just wanted to be sure and post the result for any future searches that may run across this.