Go look In my oldyeler photos I think pics are there of some of it. I can put a 205 in the trunk if I want to. I sent Alan some patterns of it made from chrismas wrapping paper.
I just wish, I had enough room under the cars rear for 205s.
I used 1/2 x 2 thin wall tubing from a scrap 5 toe office chair base to make part of the battery box and flat spring scraps to inclose it on the forward side tacked on at a 45* angle making a grill like section thats very light and strong.
I inclosed the wheelwells with nylon liners and the side post stobs hold the forward pannel cover on and give you a place to hook up jumper cables if needed .
It just kinda happened I didnt plan it that way it just evolved into a nice setup as I progressed
I let it become what was needed. I did do a upgrade on the box while I had the beam off. I move the battery strap bar forward away from the top battery post ,to make it easyer to get tools on the cable ends. also it gave the bar much need clearances in the event of a colision the battery post could have shorted across it . NOW thats not likely..
Its a tight fit under the headlite tub ..but it will fit in there and can look nice..
A 356a has the battery in the center of the trunk floor .I like the factory style trunk floor but I moved the battery. to make putting the spare in easyer.