Thanks for the replys.
I looked through photos of various arms. What I have is a two piece arm. The arm part with the headshell on it says Thorens. It looks like a TP63 or TP70 arm that I,ve seen in photos. The photos of the Tp16 I've seen show a large headshell. Apparantly Thorens would take the same tonearm, change the headshell and use a different tonearm number. I did not see any photos of the headshell on my arm which is connected to a 5" length of arm tube.
I am thinking of buying a headshell/arm combination for TP 63 0R 70 plug it into the other arm section. Based on photos they have a fairly standard cartridge mount.
Last resort is to modify the tonearm I have. Drill holes etc. but don't know if that is sacreligious. It's a bit above my level of expertise.