I don't know if I'd go as far to call them all "clean" hehe These are the original set of displays I did for the shuffle alley I have, some were done a bit quick-and-dirty just to prove the concept. If you take some care, you can get components lined up nicely and decent solder joints.
Early Stern DA-100 and Bally AS-2518-15 boards often had the 2.2k digit-driver pull-up resistors soldered in-parallel on the back of the board. Either as a factory modification or recommended modification that made it into later revisions of the boards. That was part of the reason I figured it's no big-deal to solder resistors in-parallel. I saw no downsides, you gain higher wattage rating (not really needed, but it's a gain) and once installed in a game the displays look every bit as good.
I had actually thought this would be the go-to way of getting the resistor values changed, much more approachable for someone with limited desoldering/soldering tools and saves quite a bit of time. With the resistors on the tape, if you cut the leads on one side short you just hold the tape in your hand, solder at the top solder point on each resistor being replaced, pull down on the tape to release the resistor, then move onto the next resistor of that value. Then just align the longer lead vertically with the solder pad beneath it, press down on the lead to get it flush with the bottom solder joint.... solder and snip them all. It goes pretty fast IMO. Of course, it does help to have a picture of an already-modified display to model off of otherwise it's a chore to find the pad locations and flip the board back and forth.
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