Does anyone know if there is a difference in length between the standrad SRi shocks and the GSi shocks?

Replaced the SRi shocks a few months ago and have been great so far but when the car received its pre-mot check there was an awful lot of play at the top mount. This was without any load on the wheels (ie it was jacked up), might of expected a little play due to the mounting design but this was alot of play it didnt have last year.

Of course didnt check the length or for play when the shocks were fitted as i assumed they were identical to the SRi shocks apart from the bottom mount. Any thoughts?