Is it possible to replace the wiper blade when the arm will only pull back a
couple of inches?

I have moved the blades from the parking position but arm on the passenger
side pulls right back and replacement is easy, whilst the other one is of a
different design and only allows slight movement away from the screen.

Obviously I could remove the arm but, according to Haynes, this could
require the use of a 'puller', which I don't have.

So is there any little trick that I can employ and is it worth considering
changing the arm?

Eric