You probably saw MY post.
My engine is a b16a which has close clearances to begi with, but my turbo's compressor outlet is clocked nearly 120 degrees differently than a normal turbo setup, and that puts a MUCH larger portion of the turbo compressor back against the block, which I had to clearance out to make fit.
In 90% of normal air/air intercooled installations, the smaller portion of the compressor will be near the block, adn require NO clearancing.