I'm continuing to work on the wire harness and address issues as they come up. I've removed a lot of unnecessary wires for features that don't apply and emissions junk. I've also added some functionality into the harness, such as the Tow/Haul feature and a trigger wire for "Valet Mode", which essentially allows me to have a dual tune switch. I have the engine in the truck right now to verify routings and how to hook everything up.
For engine mounts I scored a set of original 1972 BBC frame stands on CL for $20! They came with clamshells, but I opted to use the clam shells from the Suburban.
The plan all along has been to route the ECM and fuse/relay box into the cabin, but leaving it on the driver side inner fender would be a LOT easier...
However, I've come this far, and I don't want to regret something like this later down the road, so I'll figure out a pass-through for the firewall and keep the engine bay clean and simple.
While the fender was on, I had to snap a pic for motivation. There is a ton to do before its close to firing, but progress is progress.