Cam i think you would be much better off just buying an 18R-g
the parts for these motors are very hard to get. i have just finished rebuilding my 18R-GEU and it was a real pain ib the arse you also have to think of how long your car is gunna be off the road when you have to wait a couple of weeks for a part. there are other small differences too. you need a new timing chain cover. rods are different from an 18R-c (18R-GEU ones are anyway. and while you are replacing all that you may as well do a full rebuild. so it would be eaisier on yourself to jsut buy the motor outright. i think there are small differences in the oil pump shaft.