Thanks for all the input folks - I will have a stab at it!
Marky, - What size ball would you recommend? Peewee, Junior, or full size?
Nickjaxe, - I believe I answered that one already when I said that I prefer to do it myself when and if I can. Just one of those things - I prefer driving to being driven, putting up shelves myself rather than getting a joiner in, keeping the missus smiling myself rather than relying on the milkman, etc, etc, etc. I have no problems with using professionals (except my wallet), and do so when it suits, but I just prefer to do things for myself.
Right then, lets get these seals ordered up ..........