Mini-starter compatibility

Guys,

My starter is in... the original cables (318 car) more or less reach the contacts on the new Mini starter...but I have to stress the cable a bit to get the connections on and I don't like the looks of it.

The old cables are held together at the end by what appears to be a piece of rubber..any reason why I shouldn't slice that? It would relieve some strain on the geometry and allow a more gentle curve...

Thanks for any advice...you guys are usually very kind about my novice questions. :D