MeMike, I think it's time.......
Hate to break the news to you guys, but building a race car with resale value in mind is relatively pointless. Racingjunk is full of beautiful cars at decent money that are not moving at all. Many have been on there almost a year with no movement except lowering the price. The general rule of a race car is that if you can recover 30 cents on the dollar you did well.
The one good thing aboot building an A body Slant car is that IF it is not a hacked up piece of junk you can always sell it minus motor/trans and someone else can put whatever motor they want in it, not just a Slant.
If you want to run low 12's on muscle only I would get the car as light as possible and build a carbureted alcohol motor. Either methanol or E-85 will work. The K-1/Wiseco rod/piston deal would be nice to have, but not totally necessary. Have Mike do a head, bore the block +.100" to maximize head flow and also make it a little cheaper to get a custom piston made. I would have no qualms aboot using stock rods, getting pistons made, and decking the block/head to achieve around an 11-1 compression for the alky. Camshaft will have to be in the .575-.600" lift range, and Comp can take care of you there. This motor will live long and happy without having to turn it over 62-6400.
If this project actually gets going I have a Clifford intake I will send you.
For a trans a 904 will be fine. Have the V-8 guts and a LBA valve body installed and you're golden. The one place I would not skimp is converter. Get a good unit built to match the specs of the motor. I would not bother with a trans brake. At this power level you will see no difference in reaction time or ET.
At the rear I would move the springs in, install a set of Cal-Tracs, and run a 28X9X15 slick with a 4.30 gear.
That should give you a mid to low 12 second car without breaking the bank. The most expensive components will be the head, pistons, and converter. If you plan wisely, all of them will still be useable if you decide to step up to a boosted motor too.