I just encountered a similar situation related to space and center speaker widths. Most of them were just too wide and would require significant changes in set up. So I let that make my choice.
I don’t know about your JBLs, but what I did was find 2 Wharfedale’s that would fit on Music Direct. With free shipping and a 60 day return, little to lose.
Been using their Crystal 4 C for past month with my Vandersteen 3A Signatures and am keeping. Both movies and multi channel SACDs sound very good, and I’m just not hearing anything that’s a horrible match. I’m also 56, and a Deadhead that saw a couple of hundred shows, so could play a part...ha. I do consider myself a pretty critical listener so I do think I would know. Good luck!
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