Bollard with G24D-3 lampholder - can I fit a G24D-2 bulb?

[ringer]

Am looking at a job to fit an additional bollard to an existing set of three. Have identified the bollard here but this has a lampholder for 26W G24D-3. The existing bollards have G24D-2 lampholders with 18W/840 bulbs. Can I fit an 18W bulb into the G24D-3 lampholder in the new bollard, or will I run into problems because the lampholder and driver will be expecting to run a 26W bulb?

 

[Sintra]

The lamps won't fit directly into the wrong lampholder as you will find the plastic tabs won't align properly. I have known these tabs to be cut of the lamps to let them fit though.

 

[ringer]

Is it easy to source a G24D-2 lampholder, and would I be able to use it (to light an 18W lamp) with the 26W driver? Or would I need to get an 18W driver to go with it?