I also built my own battery holder (but for a rather different reason). I am not a fan of putting a battery in the direct path of the hot air off the radiator (heat KILLS batteries) and I also added a storage box so I built an insulated firewall (all the way from the hood down the tunnel to the pseudo skid plate) and put the battery. isolator and all the wiring behind that. The battery is on the right just next to the glove box. There is just enough room for a Group U1 (35 Amp Hour) battery. I used a small fuse/relay box and put it in the glove box for easy access. All accessories are relayed to come on with the key and stay on for 15 minutes after the key is turned off and I have an on/off override switch (AKA Retained Accessory Power like in a car) so I don't have to have the key on and don't accidently leave anything on for more than 15 minutes (I am getting old

). It runs everything I added except the S&B Particle Separator (I elected to leave that on the main battery)...
Where did you source the fuse block with timed relay?
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