Hey !
I fitted aftermarket turn signals, ( got them at a store downtown ).
Rizoma was too expensive for me ( 90 bucks per indicator ) paid 80 for 4 indicators its just some other brand.
You will have to cut the wires at the end, remove the stock indicators and fit the new ones. Its not that hard, just make sure you have the right tools to do so. I had to drill some holes ( next to the stock holes meant for the stock indicator. )
Remember that if you remove all the turn signals and fit the front ones first, they will automatically blink faster, and once you fitted all indicators the rhythm will be right again.
So yes you will have to cut the wires and put them together with the new indicators.
I hope this helped !