I tried filling a blue steel lamp with lava by right-clicking the source block as specified possible in the 1.7.10 wiki. However, nothing happened. Not entirely sure it's a bug, or if it's just removed, It would be a nice feature anyways.

Mod: TerraFirmaCraft-MC1.12.2-1.7.9.167
Forge version: 1.12.2-forge1.12.2-14.23.5.2847