I've got the 34/78 1050 and am using the billet aluminum hold down from PI Motorsports. There are other hold downs available as well, but you will need a hold down device compatible with the battery, and adapt it to the tray.
Also consider obtaining an Optima charger. If you ever discharge the battery completely dead, the Optima charger has a charging profile that can resurrect a dead Optima battery. Regular chargers won't do it.
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