Thanks Guys, it's FlyTampa's CYUL ad4 file that I first started working with. I'll try switching the primary number. At this point, I worked off 24 and kept subtracting 7 degrees for each runway until I reached Runway 10. It worked, in terms of opening runway 10/28 but I think I was still seeing 6L/6R open when strong winds were set out of the west - in an effort to check Rwy 28. Let me toy around with tom Gibson's suggestion.
Just home from work, tried it out. I can switch the primary runways from 24 to 6, but the heading still shows 222 - attached to 24L/24R. If I try and change the actual runway headings in the runway properties, the actual runways go WAY out of alignment.
So originally I started with runway 24 and started subtracting 7 degrees for each new runway until I reached runway 10 - 87 degrees. That's 222, 220, 213, 206, 199, 192, 185, 178, 171, 164, 157, 150, 143, 136, 129, 122, 115, 108, 101, 94, 87.
I'm not quite sure why I didn't subtract 7 from 222, but that's what I did and I now have runway 10/28 running. But it seems to me like I've not done it properly or as efficiently as I should have.