If you cannot find that scoop SLIXX has a good selection of resin ones.
I usually use the T/F Hemi block and valve covers out of a funny car or T/F kit.
I add the lower intake out of the Revell Carpenter '55 drag car or any of it's derivatives. Then I add a spacer on top.
If you're able to get one of the T/F kits I mentioned you can use the blower as is. If not you need to add some length to the rear of the blower. You don't need to be neat as the blower blanket will cover it.
I have tried to build them as accurately as I can but finding reference material is almost impossible.
If you have any other questions hit me off the board.