The tech who performed my crossover refurbishment found a company that offered a kit replacing the caps as per a Klipsch-published spec sheet, so that’s what was installed. (I’m away from home for a few days and (memory cooperating) will take a look at the brand name when I get back.)
I simply unscrewed the crossover bases and handed them over.
I don’t know what Klipsch used in your model iteration but in 1978 the factory used lamp cord to wire the crossover components…..as well as to interconnect the horns and the woofer (!).
So, I measured all those lamp cord segments and had the tech fabricate audiophile quality replacements for them all. The push-type connectors for the horns were a breeze to replace but the woofer wire replacement required opening up the woofer chamber, carefully melting/removing the old and soldering the new wires.
Due to the long break-in period any immediate results were tentative, but I thought the new parts noticeably opened up the sound and now, after a few years, they sound great to me.
That enclosed space is the biggest issue and I've dealt with it by hole-sawing a horizontal row of six 2" openings in the upper back, behind the drawers (which conveniently fit CDs). When operating, I always prop the doors open and position a quiet, small floor fan in the front to basically supplement my heating system in the winter.
At one time I had a small computer type exhaust fan mounted in the upper left, when I had a CJ PV2ar preamp and MV75 amp in there....which necessitated cutting holes in the lower left floor and allowed a cooling air flow pattern.
Being a mechanical engineer whose interest is heat transfer, please believe me when I say that issue has occupied a fair amount of my time over the years.
BTW, I started a thread by asking if there was an optimal temperature that tubes need to be most efficient, and brought up the fan.