Yes, make up your mind on ERA, forget SPF and BDR, you won't have half the fun building those. Do a painted roller, not a turn key .. more fun! Not too many hours to finish it. I have wrenched on all three of these brands and the ERA is the easiest to work on, BDR is tightest under the hood. Apologies of course to fans of these other two, but this IS the ERA Forum
Do the rear mount battery. I'd have them upgrade the 2 ga. battery cable to something bigger, 1/0 ga, maybe. If you're going to use a monster FE, I'd do a 1/2" fuel line vs the stock 3/8". Also, If you're building a torque monster, see about getting a more robust differential from CWI. Call Mike Bontoft and talk about it. Cheaper to do it up front than after you twist the axles off like I did
I have the inboard rear brakes, think about the ERA design rear suspension with outboard brakes. I'd do that if I were starting over. If you do any tracking, I'd see about the 12" front brakes (Sierra?), still keeping the 15" wheels. Again if you are tracking the car, you will want heavier springs than the 250# jobs that ERA supplies. I forget what Rick Lake told me at RnG, I think he said 350#, but he is the expert for that question.
Go with the six pins if you can afford it. More authentic, and a good feature when it is time for resale.
If you plan to do a lot of your own work, you will have the tunnel and rear cover off a bunch of times. I have literally worn out the screw holes in the floor and the nut plates in the rear bulkhead. I would ask ERA to install them with DZUS 1/4 turn fasteners. I am going to do that just as soon as I get the next rush of energy. In other words, not any time soon
When you get it running .. drive it a couple months without the interior until you get it completely sorted out. You might be yanking the seats, tunnel, and rear cover a lot.
Sam