Now, I've two worm driven slow motion controls as detached from a new Porta-like mount, and I also have a ball head, but I will need some ways to put it on the Mark-X.
In order to do that, I've ordered two 6061 aluminium bar of 2cm * 2cm, with that kind of thickness, it should be able to provide shake free attachment. These solid bars were not cheap at all, but then it's still only 30-40% of the price quoted by a local machinist.
All I will need to do is to drill two holes to mount them to the Mark-X, and drill two more holes to put on the slow motion controls, and maybe one more hole to put on the ball head.
Actually, I've an 9mm thick solid alumnium bar at home which could be used. But after drilling the holes, its wall thickness near the hole became less than 1mm (with a 1/4" hole) which is just too dangerous and will break suddenly without any warning. So a 20mm thick bar should leave some more safety margin.
Updated on 2012-1-3:-
Due to the new year holidays, the package arrived today finally.
On fixing to the Mark-X, my existing M5 screws should be long enough since the existing mounting hardware is exactly 2cm thick.
On fixing to the slow motion controls, I will need four M6 screws which is slightly longer than 2cm, and 2.5cm should be about right.
Updated on 2012-1-7:-
6061 2cm by 2cm aluminium block is harder to drill than I imagine.... anyway, persistence is king.
For the first block, I didn't lock the metal block firm enough and it was released suddenly and it hurts my hand lightly.
So for the second block, I used a clamp to fix it in place, and in order to attract all those metal debris in place, I have placed the metal block in a cup of water before drilling, and keep adding droplets of water to reduce the temperature increase during the drilling process:
Drilling holes through thick metal block using a hand drill is difficult and it's hard to be very accurate.
The attachment was firm and secure, but the metal block was a little bit too thick such that the polar scope cover could be fully screwed into place afterward.
Later I found that I just don't need the dovetail saddle, and all I will need to do is to mount my Ranger directly to the M8 mounting holes on the slow motion control. I've drilled a hole on my Ranger mounting ring in order to do that.
On the other side of the Mark-X, I left opportunity to mount a camera ball head or another slow motion control.