89 SN 351w engine replacement

1989 Ski Nautique 351w engine replacement issue. I assume the ’89 is standard rotation. What is difference between long and short block?
At first use this season plugs were “apparently” left out; ran about a mile, engine overheated and when back at dock discovered oil filter had blown off and oil all over the bilge. Cleaned up the mess, new oil filter and oil. Boat starts but has a knock in it and temp goes up quickly
Without even looking at the boat marina says I need a new engine. I know they’re probably right but would like forum’s comments also. Marina says replacement engine for ’89 Ford 351w will probably be hard to find.
Found this on the web: https://spprecision.com/products/351-windsor-long-block-crate-engine-sale.html
“core” would have to be sent to them and would have to be OK. They would rebuild in about a week; long block $1500 and short block $800. Designed as “crate engine”.
Does Forum have any experience with this company and if so what? Not shure what is exactly meant by “ok core”. What are my chances of my core being “ok”?
Thanks gang; this is my first post.
Jerry

Since Short block is 800 and long block is 1500 I suspec the long block they offer includes the Tin, Oil Pan, Valve covers, Timing cover but you need to ask them.
700 to add just heads and valve train is very steep.
Check around, ATK, Jasper Engines and many others can offer you this engine but as Pete already stated your transmission will tell you if it is Right or Left hand rotation.

Here's a link to the place you referenced

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It seems to me that it's an automotive long block and when they ask for a core to be sent back, yours won't be worth a plugged nickel to them because it was in a boat with water flowing through it causing 30 years of corrosion that doesn't happen in a car/truck with antifreeze in it..

You'll end up paying more because of that

Stick with one of the places already mentioned selling a marine long block and they won't want your core so no core charge will be involved. A number of people have used ATK with good results.

And don't even think about getting rid of any of the parts that bolt on to the long block till the job is done.

You'll need the oil pan and oil pump pickup and also the timing cover that has provisions for mounting the raw water pump bracket to mention a couple of things.

I seem to think it's been mentioned before, but why not see what might be wrong with yours first, instead of listening to somebody at the marina that hasn't even looked at it and wants to bend you over and well you know   

Here's a link to a normal rotation 351 with a 1 piece rear main seal with the standard output heads which would match what you have now. Price includes shipping and there's no core charge

It's a later block with a dipstick hole in the block under the #7 spark plug hole, that you'd need to plug but that's pretty easy.

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