Sorry, it is me who is late to the game here.
Actually, you can easily shorten the Corkscrew by cutting coils off with a box cutter and use the spare end cap included with the kit which is stapled to the instructions in the small clear bag.
However, the Innerwear needs to be sized more accurately for the proper performance. If the girth is too large then you would need to resize appropriately. We offer a healthy discount for resizes so definitely get in contact at the support email to make arrangements for that.
You can do the pinch test (as seen in the pic below) for the proper fit and note the excess silicone on either side, which in the case, indicates two sizes too large.
For your reference, each size down 28-26-24 etc is 1/4″ tighter in circumference.