Hmm. Try horizontal placement above motherboard? Or at the back of case, above cards, if there is enough clearance.
And how high is 5.25 bay slot enclosure - not enough for res? (especially if you make round hole in it's bottom to half-sink res below 5.25 bay floor ..)
Though if there enough clearance among sidewall and card, maybe you can attach res clamps to sidewall (currently taken off in this pic)?