i had a similar experience with clear ice while instructing, unforcast. Don't use flaps, keep your speed up, stay high on the glideslope so you can trade that for speed if necessary on final, use a long runway, may have to open the small side window or cessna windows cause you probably won't be able to see out front. The radios will also sometimes get pretty staticy cause of the ice build up on them. If you have to descent through icing, do it fast. Be careful in the flare since the airplane isn't so aerodynamic anymore and ice adds a lot of weight to the plane. I know a cherokee will carry a lot. Had half an inch on one once, pretty nasty but don't panic and you'll be alright.