I used the 641-2196 studs that the OP mentioned and they were (so far) a complete success for adding 1.5 inch spacers to my front end. I went to my local NAPA and the counter guy could not have been more helpful.
Do you think it would be a dumb idea to clearance the bolt hole on the plate just to get the bolt to go in straight?
The tension would still hold the plate, I would think.
