i did mine with the eyeometer. no measuring required. just bolted in an empty tranny case to the cross member, attached the csr shield, bolted up an empty block & jacked it up til the csr touched the tunnel, attached the motor plate to the block & welded in the mounting tags. i used comp eng motor plates & they slipped nicely between the rails. stock oil pan could still be fitted whilst the block was in place. tooo easy.