Anyone Know What These Parts Are?

They were never used in turbo buicks up to 1987. Mostly SBC, as shown. BBC have the slots 90 degrees to the SBC and are offset due to the BBCs angles difference from intake to exhaust. SBFs look different and lighter in mass. 4.3 chevies used them, that's prolly why they were in the box, the person was going to try to do a cheap hyd roller conversion on a buick, not knowing that the lifter bore spacing is wider on the Buick.
With the spacing only about .050" wider on the Buick, I think that widening or removing the outside of the slot would allow them to work, depending upon the lifter bore height. If so, then a 4.3 hold down spider might work.
TIMINATOR
 
the black part in the center below the carb to thew intake....
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