Cat and dog interaction.

We've got a border collie mix that at this point stays outside 90% of the time. She really seems to prefer it as she has so much more room to run. We guess her age to be about 8 years, she was adopted as an adult from a shelter. We're hopefully going to be buying a much more spacious home and would like to have her inside more often. We're concerned about her and Simon our kitty interacting. Zowie can be extremely territorial with other dogs, and has been known to attack other dogs.(There was once instance of attack when she was new to the family, since then we have been very careful to keep her seperated from all dogs.) She apparently tend to tolerate cats well, but we're worried anyway. Simon is one of those confused cats that think they're dogs. If she were to decide to attack Simon that would pretty much be all she wrote. Zowie is close to 70 pounds, and Simon weighs around 5. Any tips on how to introduce them? If we should at all? There may be a viable option if we get the house we put a bid on yesterday, we could effectively cut the house in half, we would rather not have to do that. My husband(Zowie is his dog, was a package deal lol) is all for keeping her outside existence going. I just worry if that is the most humane thing to do.
Just a side note, we do bring her in during bad weather and change her water twice a day as well as feeding her twice a day.

Perhaps the information in this thread will help.

Dogs & cats can get along very well. I have two dogs (60 lbs each)and two cats (plus birds & frogs). When I introduced my dogs to my first cat Snowball (aka Spastic Kitty) I kept them segregated at first. When the dogs were outside, the cat was allowed to roam the house. When the dogs came inside, the cat was put into another room. This way they all could smell the others' scent around the house.
Another thing I did was pet them. First I'd pet the cat, then I'd pet one of the dogs making sure to stroke their muzzle where they could get the scent of the cat. Then I'd go & pet the cat. As they all enjoy being petted, they assimilate the scent with something good and also get used to each others scent at the same time.
When I did have them meet face to face I made sure that I had a lot of small treats with me (both dog & cat). The dogs realized that treats were much more interesting than the cat. For the first while I still kept the cat in a separate bedroom with me at night & separated them when we had to go out. Dogs get kitchen & basement, cat gets bedrooms & living room.
Now my one dog Tasia (a husky cross) who barks furiously at any other living creature (including Snowball before we rescued him) & is quite overprotective/jealous gets along fine with the cats. Sport (bit of everything) my other dog loves the cats & follows them everywhere sneaking a kiss at every chance.

Well, I've noticed a recent behavior that gives me hope that they will coexist peacefully. While we're having nice weather we leave the windows open. Simon loves to sit in one particular window that he can see Zowie out of. They will sit and watch each other for a good long time with no aggresive behavior from either. (Zowie is a barker, if she thinks something funny is up she barks, yips, growls you name it.) Is this a good sign? They've also been face to face a couple of times through an open door. Simon sits inside, and Zowie sits outside(on a lead for this) and they just stare. Zowie has made those impatient "lemme go see" yips, but NOT her threatening "I'm gonna get you" type bark/growl.

This is a good sign right?