I have a question for you I recently purchased a metro 32" the sales slip says model M3213KA Serial # 411080. I take it the M stands for metro (or model) 32 is for size of cut in inches 13 should be for the hp engine. Now for the question I know the new metros have a 13hp v twin why does this mower have a 12.5hp single? If it was supposed to have a single why use the above model number? If not how do I get the V twin?