Still a one man job without it - see my web site
The cable tie approach took me some 45 minutes - three+ turns of the cam gear translates to 13 or so cable tie repositioning steps, as you get 90 degrees from each repositioning.
My 45 minutes included breaks for messing about with the dog.
It's not clear to me where the illustrated tool would attach - it appears to have two bolt holes for that purpose.
While my pictures illustrate the job on a 116 engine (380/500) it would be much the same on the 420/560.