Thanks guys, #450's are on their way as I pretty much got there with Fibanachu's formula too, before I saw the suggestion to call Speedway. The supplier of the #350's was nice enough to take them back. I am definitely going with 15 inch wheels, probably 6 or 7 wide (need 5 on 4-3/4 lug pattern and not a lot of offset, although maybe a tiny bit as I like the deep look they used to call punched or reversed. Used to be steel wheels like that everywhere, but not anymore. Your help here is much appreciated. Stay tuned, I'll report my further adventures.
Craig