I need a good arm to mate with a modified Lenco L75

In the hardcore Lenco cult (I mean that in the good sense ;-), the TransFi Terminator is developing the reputation as a great arm for the table. Unlike the Eminent Technology---also a linear-tracker of course, the TransFi is positioned on the rear of the table, running left-to-right, not front-to-back on the right side of the table.

bdp24, The position of the LT tonearm might only matter if you are using a Lenco still with its original plinth where the chassis is supported on flexible supports.  Most guys who upgrade are using massive unsprung plinths; the tonearm could be mounted anywhere without much effect.

True Lew, but I wasn't thinking in terms of the moving mass of the arm wand (one reason the VPI tables, especially the TNT's, were a great platform for the ET arm). I mentioned it 'cause I never liked having to bend over the table and look sideways to see the stylus for cueing, etc. It's nice having the arm, cartridge, and LP groove facing you! But that comes at a price---the Terminator sits over the platter, requiring care in getting LP's on and off. Being a longtime Townshend Rock owner, I'm use to that!

How about the best vintage best midvintage and best modern. 3 arms total. Ortofon/Sme Sumiko/Micro and Graham or Talea?

I have an SME M2-12R and Triplanar VII on my Nantais Ref II. Both sound terrific. I’ve mounted Graham Phantom Supreme on there, too, and that was also excellent. Like others have said above, if the table is modded to realize much of its potential, it will not limit the choice of arm.