It’s possible to convert a ¾ bed frame to accommodate a standard full mattress. Most custom retailers offer bed conversion kits and are usually familiar with the expansion process. Conversion kits may make it easier to find a mattress to fit your antique frame. Before you purchase your kit, take a picture of your vintage bed’s components before and try talking to a salesperson who understands the conversion process. They will be able to help you find the proper tools for your bed.