Wood's '408' low-buck Magnum build!
The only problem I see with you choices is the pistons. They are for a LA block which has a taller deck height. Those pistons MAY stick out of the top of the deck. Their compression height is 1.465. You may have to use a thicker head gasket to get the compression you want. ICON does make a Magnum specific piston with a 1.445 compression height. The flip side to those is you have to bore at least .030, since they do not have a standard bore available. The only other option that might work is to go with ICON's FHR series pistons. They have a 1.450 height and are available in standard bore sizes, and budget friendly. The FHR's are not their premium piston, but still a good piston from my research. I just went through this myself, so I know the choices you are facing. The only other thing I might suggest is contact Scat directly to buy a kit. They did a piston substitution for me at no extra cost, plus met Jeg's/Summits discounted pricing with free shipping. They may even be able to custom build you a kit. Also, their price for balancing is better then my local shop by a considerable margin. Just things to consider.
United Engine Machine IC9977.STD: Chrysler 408ci FHR Forged Pistons 23cc Dish | JEGS