Quoted from SealClubber:
Since there is no club started, I thought I would add one to help those of us who are trying to build one, and for those who already have one.
Since finding 12 classic Stern stand up target assemblies will be impossible, what is everyone using as a compatible substitute? Can we use modern Stern or B/W target assemblies as long as they are front mount?
For the most part, a standup target is a standup target. I bought some of the repro square target plastics from someone (named Bob) linked to on another thread. Then I bought some Williams units from Ebay and swapped the plastic targets out. The Williams units are front mount and have a diode installed. The difference is that the two holes in the mounting bracket are "front to back" instead of side by side like the Sterns.
The Williams units also have the foam impact backing behind the switch.
If you are going for original look under the play field then the Williams brackets will not work for you. But they will work. The main reason I went with these it that they were cheap on Ebay.
However, Steve at Pinball resource has a Bally "Stand Up Switch Assembly with Reversible Bracket" that looks like it will work. You will need to buy some of those repro targets and add a diode. The part number is: CA-10255-X. The problem is that they cost $6.60 each. The repro targets are about $1.50 each. That's $8.00 per switch. You need 11 for a total of $88.00 worth of standup targets !!
These do look like they are the "correct" side-by-side" screw holes in the mount bracket.
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