Clay,
" service block " is a general description for an "over the counter replacement" block , available from Ford dealers or ford parts houses....engines designated for equipment use (pumps, generators, etc) are also sometimes described as service blocks.
Converting a hydralic lifter block to a solid lifter block is just a matter of tapping and inserting a hex plug in the lifter
oil galley....
Are you sure you have solid lifters?
KK