Hi. I have been an avid reader of this forum for a few months now and find it very informative, often amusing and sometimes frustrating when it goes off thread, but always a good read.
I have just registered so that I can reply to this thread, as I own and use a Tom Senior Dividing Head.
Ian.
The spindle has a No.2 Morse taper so will accept Myford type collets, but you would have to make your own drawbar for them.
The nose is threaded 1 1/2 x 8 tpi Whitworth form which is the same as Boxford (not Myford).
Hope that helps,
Keith.