Beseler 45MCRX Enlarger - Help Assembling

I have had this enlarger in storage for let's face it, decades. I am now moving and am looking to give it away, but need to determine if it even works. I have the base/structure assembled and the head/condenser was really well packed and covered.... the motor works, but for the life of me I can't figure out how to attach the head assembly to the structure. I may be missing a part, and there is a mystery broken piece (circled in red) [Note that the bolt is just propping up the broken piece]. My memory is the flat thing sticking out of the head unit slides into something, but I don't see anything appropriate for that. Any ideas what I am missing? Thanks.

I found this doing a google search:

 

Beseler 45MX / 45MCRX Enlarger Instruction Manual

 

I am one of their customers, having bought the manual for a Beseler 23CIII Dichroic enlarger from them.

Thanks for responding Vincent. I already ordered that manual today (from that site) while meanwhile a friend sent me a link to a pdf (which is what I had been hoping for).... if of use to others it is: http://www.jollinger.com/photo/cam-coll/manuals/enlargers/beseler/Beseler_45mxt.pdf . It is for the MXT, but it proved close enough.

 

Turns out that bolt I used to prop up the broken part (which I think was broken long ago while I was still using the enlarger).... is all that is needed to attach the head unit. Given it is kind of heavy, I was surprised that is all that held in on, but that seems to be the case. Seeing the pic from the manual (and some minimal text) helped me determine that.

 

Anyway, again thanks for responding. I think I am all set now.