Bought this complete engine and robbed the carb and distributor for my 60. I have no use for the rest of it. Is it worth stripping and having the block crack checked before selling or just sell it "as is"? Came out of a '38 COE, 3-3/16 bore.
That depends how much your time is worth to you vs. how much more you could get out of it. There's more time and money in it if you do all that. You could probably use that time and money on your project and never miss whatever extra profit you might make off that block. Just my .02
You can mag it yourself, all you need is a couple of rare earth magnets, some magnetic powder, and some type of atomizing applicator. I wouldn't dis assemble, you can just do a quick check from the cylinders to the valves across the deck. Area must be clean and dry for it to work. Hitting it with a wire wheel works just fine. Even if there are cracks, it doesn't mean it will leak, its just means that there is the potential to have a leak.
List it locally for $125. take $100. If it turns over, and there are no visible cracks, everyone wins.
This is the ticket, but list it based on what they go for in your area. They may be more valuable and less common in SF CA vs. IL. I know folks in MA tend to ask more for flatheads than folks across the border in NH or ME. I'd check it for cracks if you've got the powder but don't word your listing in such a way that you guarantee it to be crack free.