Hello,I had occasion to install a set of these sealed power guides last July. I drove the original to the block out with a bit in the air chisel, cleaned the bores out with a wire brush and let the block warm up in the 100 degree temperature in front of the shop. I chilled the new guides in the freezer for about 10 minutes,then gave the bores a shot of WD40 and drove them in with a two pound hammer and a piloted driver. My machinist friend loaned me two hand reamers and the handle to turn them with,only a very light cut was required. I would buy these guides again,the fit was good and easy to finish ream. James