I have a 66 inch First Choice. I use it behind a tractor with 40 PTO HP. Engine RPM's really fall off when lowered all the way down in vrigin soil. Good luck on getting a 60 inch to till with 13.5 PTO HP in any type soil, loose, established garden or virgin. In my opinion you will have a problem with a 48 inch with 13.5 PTO HP. Tillers are some what like a Rotary Cutter or Bush Hog, they like 5 HP per foot of width this is why KK recommends 20 PTO HP for the 48 inch.