as aimez has said if the bulb holder doesnt fit in the lens then you need to cut the twowires and join to the new side repeater
Right, back to this again. I got my side repeaters off 'rashcupra' and fitted them tonight.
If the bulb holder doesn't fit the lens, a simple compromise is to get a junior hacksaw and cut down from the top of the lens so there are two nicks. This does enough to enable the bulb holder to be forced into the lens. It's a good, tight fit and won't come off.
Next wrap the bulb holder and lens with electrician's tape to seal the two bits. Then refit. No cutting wires, etc.
As it happens I have fitted chrome bulbs in place of the clear ones. Find them a bit dimmer than the orange ones, but I didn't have any orange ones lying around.
So if you ever want to, unwrap the tape and refit the other (orangy) side repeaters. No damage done!