It appears that you plan to feed the bobtail curtain at the bottom of the
center vertical. There is an alternative: feed the top of the center
vertical, where the impedance will be close to a coax match. That will
require attention to transmission line dress to minimize interaction, but
may be simpler. May also require choking currents on the coax braid.
Many different implementation options here.
For bottom feed, high Q will be more selective, but require returning more
often across the band. It is a very high Z point. I suspect that if you
have components on hand for two different LC ratios, you should experiment
and discover which you prefer.
Hope this is useful.
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