I just looked at the picture, and it appears to be of a standard printed circuit padmaster type layout. These typically had a single sheet with all the pads, another sheet with the component traces, another sheet with the non-component traces, and another with the silkscreen layer. Pins are used to align the sheets when doing the layout (and photo reductions.) The padmaster is laid out first, and then the other sheets are done with the padmaster on the bottom. The usual way of making the soldermask artwork was a bit more involved. A "picture" of the holes in the drilled board was overlayed with 1:1 photo positive of the padmaster (to block out the holes in the pads) and the resulting "picture" was made into a negative which was then blown up photographically by the amount needed by the PC house large enough (usually about 0.005" - 0.010") so the soldermask wouldn't bleed onto the pads when it was silkscreened onto the board. Yes, dry film solder mask could have been used with a smaller enlargement, but it was not generally used on high volume production boards (too pricy.) Also, the adhesive on the tape tends to dry out/become brittle with time, so I would be *very* careful in handling these layouts. Any engineering photolab can reduce them to 1:1 positives and negatives. When you find a PC shop to manufacture the boards, they should also have the contacts to get them reduced. Again, unless you have the drill drawing, you will need to make one. *Usually*, different pad sizes were used for the different size holes. Double check the final artwork to make sure that a piece of tape didn't fall off the original artwork. It will usually be "obvious" since there will be either pads with nothing attached, or traces that just end. FYI, another way of laying out boards was to use red and blue tape with black hole pads. One color was used for the component side traces, and the other color was used for the non-component side traces. The artwork would then be done by using filters to create the photo artwork.