Considering Repowering Again

Back in 2015 I considered Repowering my 54' Donzi Sportfish when I had a failure with the existing STBD Detriot 12V92TTA. For various reasons I decided back then to rebuild the Detriot. The rebuild was successful and both engines have been operating well the last four years (knock wood).
Despite the engines running well I continue to have the itch to Repower. When I bought this boat in 2012 I loved everything except the Detriots. Today, I love the boat even more as we have continually upgraded and improved the boat every year. Although the engines run well I am fearful of issues as it is difficult to find people still working on Detriots. Further, the DDEC system is near impossible to service and find parts other than getting lucky from Sturdy or Ebay.
One of the reasons I didn't Repower is when I considered it previously I really wanted to increase HP and that was a major undertaking. Fast forward to today and I'm realizing life is sometimes better without needing to go faster. In fact, I go much slower often now. So now I'm exploring Repower with the 1150 hp CAT C-18 ACERT engines and ZF Trans.
I'm confused if my existing Detriots are 1150hp or 1080 hp. There is conflicting info. I can find documentation on the 1080hp but coming up empty on 1150 hp 12v92TTA. Anyone shed some light here?
Everything I read on the C-18's is pretty positive. They are about 800 lbs lighter than the Detriots and I would be able to get rid of all kinds of additional stuff like remote trolling valve actuators with cables, lots of electrical wiring, additional 12v batteries and chargers just to run the 12v DDEC stuff, etc, etc. I bet I would easily shed 2,000 lbs off the boat.
So my thinking is if I can stay at the same HP, keep the existing shafts and struts yet shed some weight it seems like I should maintain current cruising speeds and burn a little less fuel. Who knows, maybe even pick up a little speed. I'm also hoping the CATs would be a little less noisy at cruising speeds??
I'm pretty set on CATs as I can get them serviced and find parts easily. The C-18s occupy less space than my existing engines so servicing should be a bit easier. I would go with C-32s in a hearbeat but I just don't think they will fit.
Any input or suggestions? Anything else I should consider?

Capt Ralph can you expand on your opinion the C32s will fit please? My research shows the C32's at 9" taller and about 10" wider. The Detriots already push the limits of my engine room. I couldn't get a length with gear to compare to but just the added height and width seems like it would be problematic. What am I misisng?

Thanks. I do have 10 degree down angle gears behind the 12v92s now. I'll have to look closer at the C-32s and possible remote mounting of items.

Well fortunately I'm in the shipyard business so lots of resources at my disposal. However, we are large commercial, not yacht so a bit different.

I appreciate all the input. It would be difficult for me to seriously consider MAN's. Not because they are not good engines but the service and parts are just not available in my area. Whereas MTU would be a little better, still a challenge. Further, I have a business relationship with our CAT dealer so that helps quite a bit.

Noise consideration is not my main objective although I would be dissapointed if it were louder.

I may be able to shoe horn in C-32's but outboard access is already difficult with the Detriots and the C-32's would extend another 4-5 inches outboard. Then there is consideration of bigger shafts, struts, exhaust , etc ,etc. And with C-32's I don't know what it would do to the handling characteristics of the hull. Would I develop some chine walking or tail walking issues? The current configuration is rock solid which of course is great.

The spec sheet I have indicates the 12V-92TA dry weight is 4,895 lbs dry. Not sure where you found the 5,861 lbs you indicate? I attached the sheet I have but I cannot confirm it matches my engines exactly. So I'm assuming roughly 1, 600 lbs weight saving from engines (800# each) plus another 400 lbs for batteries, chargers, and other stuff that can go away.