We just cut the side off so you can side it in from the side. The blowsion cable is way thick to ever make it through the hole. We didn't cut it as big as the hole, just small enough where the cable popped in with a ton of pressure, then stayed in. So like 1mm or .5mm smaller and hook it a bit.
Only takes a sec. Just don't cut it too wide. Start small and keep trying to force the cable in. If it doesn't fit, just file until you can get it to pop in from the side.
If you went to big and it just slides right in from the side, then just run a zip tie around it holding it in.