Mike,
There are a lot of threads here on the subject of steering lube grease.
To drain the old oil, make sure you only undo the front plate slightly - not more than 1/8"+ or you can unseat the rear bearing with destructive results. Ask me how I know. Others have had the same problem.
I see Moss has no info on how to load the Dynolite. I've used both John Deere Corn Head NLGI 0 grease and Stens (sold under several names) 00 grease. The corn head injects from a grease gun cartridge with a grease needle injector on the end of the hose. The 00 comes in a quart squeeze bottle, which is pretty easy. You attach a short piece of clear tube to the bottle which will reach the bottom of the box and fill it from the bottom up. Make sure you've turned the wheel all the way to (IIRC) the left so your tube will reach all the way down.
Microwaving the bottle or leaving it in the sun helps liquify it. You fill the box part way, then run the steering lock-to-lock to work out the bubbles, then fill it a little more - until it comes out the upper plug. Keep working the steering until all the air's out. Jacking up the front of the car makes this easier.
If you must use the Dynolite, you might be able to use a turkey baster with the same extension tube and make a piston from a piece of dowel you could use to force it through the baster into the box.