Aux Battery Tray Installation

[805.K10]

Unfortunately it seems the original auxiliary battery tray is no longer available.  A retailer sells a battery tray that can supposedly be installed in the aux position - basically it's a right-side tray. They also sell the battery support for the left-side, which I have. It's strange how they have the support, but not the tray[?!].

My question is has anyone installed this tray on the left-side aux position? There is one hole that lines up, but it is where he battery sits. I would like to see how others have tackled this install issue before I start fabricating. I've also reached out to the retailer, but haven't heard back from them.

model: 75 Chevy K10 

update: guess we can't mention a specific retailer