The 59 I just picked up has the 223 I6 with the 2 hold down nuts like a Y block valve cover. The question is the 2 P400's I have (59 & 61) also have the 223 (I always thought) but the valve covers are bolted around the edges of the flange. When did this change occur if it did and what year did the 223 come out? I saw a 53 Aluminum Bread truck with the 223 over on the HAMB. I thought it came out in 54 with the Y block.

55 Vicky & customline

58 Rack Dump, 55 F350 yard truck, 57 F100

59 & 61 P 400's, 58 F100 custom cab, 69 F100, 79 F150, 82 F600 ramp truck, 90 mustang conv 7 up, 94 Mustang, Should I continue?