CP is where 20 HP and under OHV and valve in block twins run. USLMRA rules allow you turn the motor. It only states that the PTO has go through the original clearance hole. Turn it sideways and add a RAGB (right angle gear box)
1) Engine must be originally manufactured for use in lawn mowing equipment and be stock in appearance, with the exception of air filter, air cleaner or velocity
stack. Crankshaft must be in original orientation and clearance hole in the frame.
Engine may be internally modified.
No, you cannot change the orientation of the engine in prepared classes. Only in FX!
4) Driveline may be modified from the engine pulley to the rear wheels, but must
utilize a shiftable lawnmower transmission or transaxle. Vari-drivers may only
be used in an original installation.
you could use a driveshaft, if you could do it without changing engine orientation?
6) No centrifugal and or torque converter clutches.
Don't forget this
22) Must use axle mounted brakes, no lawnmower transaxle or transmission
mounted brakes.
Nope, couldn't put your brakes under there.
Now with all the legality covered, I must ask....Why?
All you've accomplished is a whole lot of un-needed weight!
Belt drive is easy, reliable when done right, and the lightest way to mow!