[Rhodes22-list] Center Board Questions and pics

[Richard Stott]

Dear List
I removed the CB cap last weekend and found some interesting issues.
The crack had been there for some time, but started leaking badly mid season last summer.
I have attend some photos to augment this discussion.
I appears the crack in the cap was caused by the board swinging too far forward, so the top forward edge of the CB was forced into the cap.
It happened before I inherited the boat and it was "repaired” with silicone from underneath.
The two blocks under the cap are bolted with long #10 screws from the bottom and covered with silicone from the top - its ugly and wrong.
The two blocks attached to the CB itself appear to be for 1/4 line, and need to be replaced no matter what.
The system line in my system was 1/4 nylon twist,  and much too stretchy. 
So here are some questions:
1. What size and type line is ideal for the CB system?
2. Where can I find those blocks that fit in the slot in the CB?
3. What stops the CB from swinging too far forward?
4. The tubes, (pieces of hosing) appear to be clear hose - they may have shrunk, or were cut short on purpose, but are an inch short of the cap, and one is very warped - what are they supposed to be made of? 
5. What is the proper installation for the two blocks attached to the cap? 
Thanks in advance 
Ric
s/v Dadventure
Hampton Bays, NY