Hy Drive leaky front seal

[tropicrows]

I have a Hy-Drive (model 101) steering unit which has developed a leak on the steering shaft of the helm unit. At first glance it looks like this can be replaced without pulling the whole unit apart. I think I just need to remove the steering wheel and front cover, which I assume will allow access the front seal.
Can anyone confirm this before I start, and might know the seal type and number/size

[Tracker]

drop a email.
http://www.hydrive.com.au/site/product-ah.html

[Tracker]

or read this.
http://www.marinedirect.co.nz/catalogue9.asp
snip>
This pump design has been tried and proven over more than 35 years to be the most robust available for marine steering.
Like the cylinders, the helms have field replaceable shaft seals. The helm unit does not have to be disconnected or removed to replace the seal.

[comfortably numb]

Gday Tropicrows,
Just wondering how you went fixing this - mine has the same problem. Im guessing it should be fairly simple but any hints you can give me?
I sent hydrive an email re spare parts today how much did they slug you? did you just need the seal or did something else need replacing too?
Cheers, Matt