I fitted a gaiter recently to my car. Having found the track rod end to be siezed in after splitting the ball joint I used a different method.
Cover the tre with a small plastic bag and liberally cover with grease. Also lubricate the inside of the new boot.
Slide the new boot on and I used a spoon as a spreader to ease the small end of the boot over the threaded part of the tre.
Not the approved way, but the boot did not split and passed the mot ok.
Nick