In this pic, I played with the contrast to highlight the shapes of the squirter humps. The blue arrows point at the four humps.

There are three basic ways to ID an L block:
...the timing cover decal will have an "L" on it
...the timing belt and gears are the round tooth type
...the four humps [illustrated and pointed out here] along the main oil galley.

Just because of those three "proofs", it is not for absolute certain that the motor block will actually have the squirters inside.

Prior to model year 1993, Volvo did install L blocks in NA [normally aspirated] and in turbo motors. Those may or may not be drilled/threaded inside for the squirters; and they may or may not have squirters. They could be drilled for squirters, but just have bolts installed to plug the holes.

To the best of my knowledge, by model year 1993, ALL turbo motor L blocks did have squirters. And all NA motors had bolts in the drilled and tapped holes. Subsequent model years followed that pattern:
...NA L blocks drilled, tapped, and bolted;
...turbo L blocks drilled, tapped, and squirters installed.

Despite all that, it still boils down to actually removing the oil pan and visually confirming that the squirters are really there.

UPDATE:

According to the parts microfiches that I have, the NA L blocks were at best drilled and tapped, with bolts in the holes.

BUT, I have received reports from several sources that NA L blocks from '94 on were drilled, tapped, AND equipped with squirters. This is very welcome information.