Thanks for your reply.
>>Don't know what you mean about mounting through the block though - that would tend to let all the oil run out...<<
Perhaps a poor choice of words on my part. I suppose a picture is worth a thousand words:
More info here:
http://www.motosliders.com/MS-1.html
As you can see, this is a very effective slider. It stands less of a chance of breaking off if you should go down.
Depending on a bike's design, this may not be possible. I'll check out the Sky King units. Thanks again.