Good advice, Bob999...
The PT-425's drive a 5' finish mower, BTW, but only a 4' rough-
cut mower. The PT-422 has a 4' finish mower available, or you could try the 5' -- but it would likely not perform too well in tall, damp grass.
On those class machines, the 60" finish mower is a 3-spindle, belt-driven design, while the 48" rough-
cut mowers have a single stump-jumper spindle, directly connected (my older design has a lovejoy connector though the newer designs are different). Not sure how the 48" finish mower is designed...
Here's a pic of the motor mounting and belt routing on the 60" finish mower:
http://mypowertrac.com/DesktopModule...om&ImageSize=5