I'm in the process of finishing my 89 mag 454 on a stand and have installed a used set of gil/hardin stock hp500 style manifolds that have mercurystyle plumbing. Im having some issues figuring out the thermostat hoses. Boat has been converted to crossover cooling but im looking for the hose/fitting combo that hooks up and doesn't interfere. Do i need different manifold fittings? Fo i need hp500 hoses? If i make them tight they interfere and have unnatural bends. If i make them loose they are floppy and not right. I can't cut because they are stepped/flared. See pics below. First Pic is about what it started as. Next couple are what I'm working with. Send me some pics of stockist setups and part numbers.

Whilecwaiting for other responses, see if this helps:
https://www.hardin-marine.com/Instru...20-901180i.pdf

I saw the hoses in that pic. But is there a pn for them?

In this application, you should do away with the traditional merc plumbing and use the GB style manifold plumbing which plumbs from the bottom of the water tree instead of the front to avoid the interference you are running into.

I don't have enough posts to post a link, but go to the Hardin Marine website then under product categories go to

Exhaust Systems→ Hardin Marine Exhaust → Gil Replacement Systems → Hardin/Gil Replacement Parts → Standard Hardin Marine/Gil System Replacement Parts

There will be an exploded view with part numbers for all the components on the bottom water tree.

I was looking at that a bit. It seems like it would work well on the one side. But the other side with the alternator and steering pump it still seems like everything wants to interfere. You're talking about iten

I would run a 90 degree fitting into bottom of #7A and run a longer hose from the thermostat housing to that 90 degree fitting.

90 degree fitting that would go into 7A would be P/N: 540222110

Yeah I have a few extra 90s laying around. Do you by chance have a picture of one all set up with my style alternator and steering mounting?

Unfortunately this is all I can really find.

Yeah my hose does not want to go under the power steering pump at all. I wonder if somebody took it and flipped it. Or if there's a part number of that hose that would be great