Naa leave well alone, it's a head off job and not worth it if it's clean. Should be good for a few 10k's before that needs doing.
The car I had was full dealer SH, had motorcraft parts and had been well looked after. Was a clean car actualy all round, but the second engine started using oil. I bought a Carlton and we traded the Sierra in against a BMW e30 325i Sport for my Bro ( think he just turned 21!!! ) AWSOME car
TT