I will take a shot at this. It appears that you have hardware which is  
newer (replaced at some point and time) than your hull. The top plastic piece 
is  screwed together. Remove the screws and you will be able to remove it. 
Order a  new genny from General Boats and it will come with a sleeve which 
fits over the  aluminum tube. The sail will then be screwed to the top of the 
tube. The bottom  is usually hand tightened with another short piece of line 
going through an  eyelet in the sail and attached to the furling drum in 
some manner. Do you have  the original sail? Seeing what it looks like at top 
and bottom would help quite  a bit. Great pictures. Anything you can provide 
will be helpful.
 
Rummy
 
 
In a message dated 10/15/2012 10:15:08 A.M. Eastern Daylight Time,  
rbeytagh at gmail.com writes:

[broken link to nabble content:http://rhodes-22.1065344.n5.nabble.com/file/n44370/DSC_0044_%281280x555%29.j]
pg