D30 Pump is cracked, from previous owner. Wish to convert to a D50) Hypro and mount it to the same 5HP Kawasaki (new) engine, before later swapping it for an 8hp. The Hypro lit indicates the pressure regulator is the same for the D30 and D50. The engine has a 3/4" shaft with an older style (1990) gear reduction unit. Does anyoone know if this is a direct swap? How far off on performance will it be with a 5hp engine? Thanks! PS: How is the hypro 13381-0011? Using approx 12gpm.