Thanks for your help matt. At least question 1 is sorted!
The serial is 841824. I dont think this amp is identical to the schematic.
I believe the 16uf 450 caps in this amp are 20uf500v on the schematic.
There is one 70uf100v cap down the bottom of the schematic just above the diamond shaped circuit. in the amp they are located under the doghouse with all the other big caps from question 3.