So I would need to replace the HL multi function unit with a Taigen MFU? You can't just change the receiver currently attached to the HL MFU?
By Hobby Radio system do you mean changing the MFU with one from a different company? I'm guessing there are specific ones you need to get? Would the Taigen handset work with those, or do I you need a specific handset to go with specific MFUs?