I have a 64 262 in the f250 I'm working on. It came with a note book with oil change and mileage info and it allegedly had rings, bearings and a valve job about 8-10k ago, but that was some time in the 90s. It has 2 cylinders where the compression is a little lower than the other 4 but my buddy said it might just need harder driving for a while as it has spent the last 20 years on a a farm. It still has the factory air cleaner with "262 cubic inch and 152 H.P. on it." I have a 65 240 and access to a 300 and they are cheaper to modify. Call me at 903-375-3957. We can discuss this further. Im tired of typing. LOL JT.