Do I really need to lift the engine out?

1997 Explorer XLT, 200,000 Klm, 4ltr V6 Petrol.
I have a timing chain tension problem and the engine is making the usual diesel sounding ticking.
I have been told by the manual and a mechanic to take the engine out but last week spoke to another mechanic who said he has done one without taking the engine out. Any help is appreciated.