Yes, you will need to convert your gas valve or replace it if conversion kit not available, also change or drill your burner orfices to correct BTU rating. Reset gas pressure with manometer to natural gas w/c specs.
You may have problems finding a kit for this furnace. Consolidated Industries went out of business years ago. The valve spring you should be able to find. You may be able to find someone who can gauge and drill the orifices for you.
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