I had to replace the 848 head on my 261 last December. After 10 yrs of trying to keep up with traffic on I-10 (65-70mph) the valve seats were hammered into the head. Lucky me I had another stashed under the bench. Machine shop that I have used for 30+ yrs., replaced all the seats, guides, seals, and surfaced the head $450.00 out the door. I am happily driving the truck again, but with the addition of World Class Borg/Warner T5 transmission, The I-10 speeds are now at 2,000 rpm.
