I got the bolt-in IFS crossmember from Speedway installed on my '50 3100. Yes, a little grinding and a very slight reaming of a couple of bolt holes. It's dead level side to side. I measured, remeasured and measured again before I started drilling...still felt like here goes nothin' with the first hole. I could envision the frame rails looking as if they had been hit with a shotgun blast and still none of the holes would match up! The IFS is back ordered until next week...wasn't ready for it anyhow.
What amazes me is how well it fit on a 70 year old truck with all it has probably been through. Credit to both companies. Now I'm taking it apart for wire brushing the rails where the blaster couldn't get to when the 216 and tranny were still in it. Satin Chassis Saver is on the menu.