10 being extremely difficult. I would say NA pump conversion and hose/line removal is a 8.5. As for the HICAS bar 5.5 because of issue were the bone used to close up the hicas line did not line up make it difficult to thread in the bolts (dremel: fix that problem) and breaking lose the tie rod from the hicas pump requires alote of force. ALOTE of patient is the key to get this project done.