They are notoriously difficult cars to work on, very limited access to the engine. Typically you're looking at an engine out job by a specialist just to replace cooling and oil feed pipes to the turbos, but we got round it by making some special tools which enabled to us to remove them and fit new ones. A few months after we fitted the pipes it had to go to the specialist and have the engine removed anyway to have the exhaust studs and nuts replaced, amongst other things so it was a waste of time
You cannot run a super car on a shoe string.