I need to replace the 12.5hp IC that came on my Simplicity (circa 1990) model#4212H (hydro). I want an engine with more HP and an oil pump system rather than splash, as in the 12.5hp IC series. I was hoping to find someone with ideas on what to use. The hydro unit is the reason I'm keeping the tractor. So any ideas on what to use?? I contacted Simplicity and that was a wasted effort. Comments and questions from the gallery.....please!