Ian, For some reason (my fault i`m sure) this got put on to the wrong section "Europe" not the MB trucks and I cant seem to move it, anyway my truck started just like yours, It had the PTO driven twin pump on the gearbox, I removed the larger of the 2 and adapted the small pump directly onto the PTO.
I spent a lot of time talking Carl from Gliderite, who I met at a nec show, he is the director and a really helpful guy.
We designed the system between us, with myself deciding where I wanted the rams and the amount of ground clearance, he sent me some sample rams the length I wanted and I welded on the mounting plates and made the mounting on the chassis.
He manufactured a tank to my dimensions and then sent out a guy to make up all the pipework, that is a slim 10 mm o/d.
To work the system, you start the truck, engage PTO and lower each leg as required, I had the system made so I can lower each leg separately as I prefer that, but He could do an automatic system.
Regarding the air bags on the front, I had to relocate the bump stops, and fabricated a bracket to mount to the chassis, and then made a loose fitting bracket over the spring, To control the air pressure, I used an adjustable pressure regulator and a gauge, mounted on the passenger seat base, so I can alter the ride height as required.
I have left the rear suspension as it is at the moment, mainly because I could not find an air bag slim enough to fit between the chassis and wheels, but I would like to be able to lift the rear a bit. Maybe in the future!
I will try to find some pictures and post them.