Wow! A lot of great information.Thank you Gents! I'm a 80 year old with no LS or EFI knowledge so every step I take is a learning experience. I was hoping to find an LS/EFI boat guy in my area that could give me some help but so far no luck. When I first mentioned using an LS for my project most of my boating friends said NO, use a 350 SBC. Well I wanted to be different and blow their socks off on the water. So here I am asking for your help. Every answer is greatly appreciated! Thank You!
I could be very interested in the Jegg's spacer. Right now it looks like the best solution. I did see these on the Hardin web site, but was not sure if I needed it. Please keep feeding me your good information. This spacer looks like it goes on the end of the crank which then would put the flywheel and damper .40 inches closer to the trans, adding .40 inch more engagement. Will that be enough?

RyanW10 I'm not sure how that spacer piece goes on the end of the crank and allows a proper flush fit of the flywheel. Can you please educate me? I would of thought the bolts would be countersunk? or are they long enough to go thru the flywheel and spacer to the crank?

The bolts go through flywheel and spacer

Ryanw10 email me at [email protected]. Might just be able to make a deal.

You have to use longer bolts, probably the ones for a manual transmission flywheel. Should tell you in the instructions with the spacer.

.400 more will be plenty.

I don't love putting more load on the bolts however. If you can find bolts with more of a shoulder on them it will help.

Thank You all for some great information. As of this moment in time, I think I'll give Scott at Hardin Marine a call back and purchase one of his crankshaft spacers that is designed to go with the flywheel and damper plate I currently have. The cost is approx. $150.00. Then I sure hope the problem is solved. I need to move on and get this boat plumbed and wired. I've held off because this fix will require pulling the engine / trans out.