I just rebuilt a 235. It was in fact 1000's of dollars. It took 4 heads and 1300 miles and right at a grand just to find a "not cracked" and usable head alone. These stovebolts are incredibly expensive to rebuild. Machine work is horribly expensive any more. I did 75 % of the rebuild and it still puckered.me up... I met alot of nice people on this journey and enjoyed visiting about old trucks and tractors with each and every one. That's is what made it all worth it!