stop by dollar general and purchase " the works" toilet bowl cleaner. It will be tough to get the boat perfectly clean. 2 bottles should be good enough. spray on and wait a minute or so then wash off. Once its rinsed, powerwash the rest
The heat stress will lessen the wire stength also.
Are Twilli tips necessary? no. but they are a great upgrade and in the long run you will see certainly see a difference.