Interesting pairing. Those crossovers are a few thousand serial numbers apart. Wonder how such a disparate pair got together?
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You'll definitely need to be replacing all the caps in the DQ-10 with the black electrolytics and the gray Matsushita 80?F. Electrolytic capacitors do not last half as long (or even a third as long) as those are old and series crossovers are finnicky enough with caps that are in value with the right ESR let alone dried out caps with eroded oxide layers. You'll want to do both at the same time to keep their voicing the same. It's not a waste, those old polyester film caps do degrade with time and forty years is about when their failure rate becomes significant ie around the age of that crossover. So, it'll need to be done sooner than later anyways to avoid risking something being off or bad.
As for the Regnar kits, the basic package uses Solens non-polarized metallized polypropylene film capacitors that can be picked up most anywhere (Madisound, Parts Express, Solen.ca, etc). Iirc, the blue 80?F cap is a Bennic electrolytic, but the brand may have changed. The more expensive packages change to ClarityCap PX metallized polypropylene film caps (again available at Madisound and Parts Express) to increasing degrees as the price goes up. They're solid cap choices and my recommendation regardless of what others may sell as a package. You could go more expensive (Janzen, Mundorf) or throw away money on lower quality, but even more expensive esoteric options like those from Dueland, but there'd be nothing to gain there or you might even end up worse off. (Audiophile esoterica has little correlation with good, competent electronic design.)
The cap values in the Regnar kits, however, are tweaked just a little bit from the last Dahlquist revision values. That was his own improvement on the design and, coupled with the customer service, a point (though arguable) to the premium pricing. I don't feel comfortable sharing those and undercutting his business in a more direct manner (no matter how small the degree may be) beyond good generic advice that applies to all vintage speakers.
