Hi Arthur,
I posted a description on what you can do at my other post (Airedales Terriers and Cochin bantams) and you can see how I did it. But since you're going to have a challenge with the westie, I think you can still use the same approach, although I don't have a Westie. Also, all dogs have different prey drives, so you'll have to adapt the methods and approaches.
I think it can be done, you just need to be 100% in total control whenever you have practice bonding sessions btw dogs and chicks. If in doubt, pull back. But it might also be a good idea if you can wear out your westie first, before introducing the chicks. Take him for a bike ride, and let him jog a few miles with you, drain some of his energy first, or let him run on the treadmill, or do what you need to make sure his energy is lower. Also, feed him a full meal before the practice session, so he will be less likely to submit to the hunt instinct.
Another way is to hold the chick firmly to your body while introducing to the westie, it will make it harder for the westie to pounce or jump the chick if it is stuck safely to your torso. If you establish firmly you are the god who is in control of all the creatures in your domain, inc all the chicks and dogs, then you can do anything you want and the dogs will have to submit to your will. That's how we run things here in my pack. No problems..
Hope you have good luck.
Sheila