If I am reading your info correct you are working on a Maytag unit. These can be converted to LP gas easily but you need to replace a part in the valve in addition to the orifice. This is called a limiter and replaces a similar part in the top of the gas valve. Make sure you do this at the same time as the orifice change. Instructions for the necessary changes are usually contained in the parts package. Also there are several videos on You Tube showing how to do this change. You will probably need to take the drum out to get at the valve and I usually take the valve itself out of the dryer but it can be done in place if you are careful. When you are working on the valve assembly be very careful not to disturb the ceramic igniter as they break easily and are expensive .