Need some help with high torque 408 build

Hello everyone.

I had originally purchased a complete '74 360 to build into a 408, but I found a sand casting flaw in the block so the block is junk, but I've retained everything else, including the 974 heads, Edelbrock intake manifold, and Edelbrock 600cfm 4bbl carb (1406 I believe, it looks like the intake and carb were a package).

I'm looking to build a budget high torque 408. The only machine shop I trusted packed up shop recently, so I want to purchase a 408 short block and build the rest from there. I've been doing a lot of research and I'm leaning towards a 408 short block from Muscle Motors. Places like Blueprint and ATK have short blocks for a grand less, but I'm seeing too many negative reviews.

So basically here's what I'm looking at doing:

Muscle Motors 408 short block - shooting for 9-9.5:1 static cr
Rebuilt 974 heads - maybe some minor porting/cleanup?
XE256 cam
Eddy intake and 600cfm carb
1 5/8 headers

Does this seem like a good combination? Is it worth investing in porting and larger valves in the 974 heads with this combination?

Any other feedback/advice regarding this combination would be much appreciated. This is my first engine build, I've spent hours looking all over the internet trying to gather as much info as I could before posting.

What kind of power would this combination make?

Thanks