Boice-Crane 2500 Series table saw (1949)

I was very lucky to find this, heavy duty, very heavy Boice-Crane, (1949) 2500 Series table saw in Victoria, B.C. about a month ago (April/10)
It runs beautifully with it's 3/4 hp very heavy duty motor.

It took me about 2 weeks to make and put wheels on it - weighs about 400 + lbs. - and put it all together. It had to be taken apart when bought, as it would be extremely difficult to move it assembled. But now, with it's wheels, I can move it in my shop anywhere I want. I also made brakes for it as I didn't want this beast in my shop to move while sawing heavy plywood.
But I have one problem. I see by pictures on the net that, while this saw is described as a 10" table saw, the saw came with an 8 1/4 " blade. The arbor is suppose to be adjustable to accommodate 6" - 8", and 10" blades.
I cannot get the arbor, with a 10" blade in it, to go lower than the blade projecting 1" above the table top. I cannot figure out how to do that adjustment even though the internet pictures seem to say I can do it - lower the arbor more than it is.
If anyone can help me I will be most appreciative.

Paul