Hey Bob
Way to go. You'll find it EASIER than 4x5. Don't forget a big darkcloth, so you can get back from the glass !
1. I use a 240 EL Nikkor. Fantastic. The only drawback with the Nikkor ( on the same enlarger you have ) is mounting plate on the enlarger had to be cut away to make room: the lens has a very great diameter. A new Rodenstock would be great as well, and I'm sure an Apo Nikkor or Konica/Kowa repro lense would be fine as well.
2. Lots of folks have used the 159 Wolly, but that was only an OK lens a long time ago. The 150 SW Nikkor is an absolute joy to use. I was MORE than delighted in my commercial days with the Nikkor ( today, I just make muddy little contact sheets with my protars ). It is VERY easy to use, the image seeming to be lasered into the ground glass.
Have a GOOD time.
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