Grant,
These are the McCauley 2 piece, 3 bolt design which is the newer (much better) version of their wheel and brake systems.
Vinnie,
My 150 is an "M" model which came with the older, 3 piece McCauley wheels and brakes (junk).
Since your 150 is an "L" model (older than mine) I would assume you have (or had) the older system as well and if so, these rotors won't work unless the part numbers match up?
One would need a parts manual on Grants plane and one for your plane so the rotor part numbers can be cross referenced to confirm this.
On a side note: I will say that if you're still using the old 3 piece, 6 bolt McCauley wheels and brakes, you're probably living on borrowed time. The center hubs from this design are known to crack (very common) and Richard Hollrah has some pretty graphic pictures showing the problem so maybe he'll chime in with the gory pictures.
Also, it's very common for owners to upgrade the wheel and brake system to Cleveland wheel and brakes (like Grant just did, like I did, like Richard did etc. and etc.) so maybe you'll be lucky and someone prior to your ownership already converted yours??
