That's really nice. I have the Grabber Orange Mach 1 too, and a Lime Gold version.
As for the S550, the only Grabber Blue one to date is the GT500 from Maisto :)
Welcome to the forum!
Firstly, your best bet for a tune is MAP. They have lots of experiencing in tuning the S550.
https://www.motorsportandperformance.com/
Secondly, if you're on Facebook, come and join us at https://www.facebook.com/groups/SimplyMustangsUK
OP. I see you list the UK in your info........sadly, for you, all UK 2018+ come with the digital dash and there is no "base" car, unless you go for a pre-facelift model (2015-2017)
The guys at Modurstang are great and they actually offer a replacement oil cooler system (as do GT101, but they're based in Essex). Finger's crossed your engine is OK.
Two other highly recommended specialists are
Motorsport and Performance (Yorkshire)
https://www.motorsportandperformance.com/...
Also, if you're on Facebook, join Simply Mustangs UK. You'll get lots of very good advice and it's a very friendly group :)
https://www.facebook.com/groups/SimplyMustangsUK
Very likely to be your oil cooler........this is not uncommon on the RHD S550.
Are you still under warranty, because it could be a big job, in as much as this has wrecked some engines :(
I don't recall seeing it posted here, but ThePill kindly posted it over on Mustang7g. Norm was active and respected on a number of Mustang forums. A little late, but my condolences to his family and friends.
Brittany Blue debuted for the '67MY........and that's a '65 or '66 coupe.
However, Ford did have several light blue metallics for those model years which were all similar to BB
This is a good reference site with links to photos of the various colors :)...