I'd think any gas services contractor or outlet should be able to help you out.. and if the propane orifice is larger than that for CNG you could just drill out the originals.. (but I'm not sure which way that works out)
EDIT.. just did a bit of googling and it looks like the propane orifice is generally smaller due to the higher supply pressure...but didn't find actual data.
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"
Last edited by Faster; 09-25-2010 at 04:32 PM.