Is there a difference in fit in the sd and sdr model tail lights? I found one it says it's listed for the sdr and the 690 but im trying to figure out if it will fit my 990. Thanks in advance guys!

Huge difference between the SD and SDR tail lights.

SDR is all led and integrated in the tail. SD is a regular light unit with an incandescent bulb.

I might post pictures tonight when I have more time to look up pictures of both.

Get one off eBay and save yourself some money. I've been running my chinese smoked tail light with integrated blinkers for over a year without issue (and I jump my bike off speed bumps and shit). It's a carbon copy of the rumble.

Here is a link to an example.

SDR 990 light



SD light