Tell your friend to skip the adjustable valvetrain and stick with stock rockers/pushrods. You can run a pretty decent hydraulic cam with the stock valvetrain.

Also while the KB236 pistons are a great choice for 440 build with closed chambered heads setup for quench, they aren't a good choice for use with 452 heads. With 452's they will give you about 9.8 compression which will be too much for an iron headed, mild cammed pump gas non-quench engine. I would either go with a lower CR piston to drop down to around 9:1 compression or do like dogdays suggests and do a domed quench piston, however they do require more work to setup properly.

Remember, the stock 68-71 440's ran a piston further in the hole to give them around 8.8 compression. And IMO in a truck you don't want it setup right on the ragged edge of detonation.