I must be sick

I have a 1994 ranger with a 3.0 and aod,actually it is one of the best trucks i've owned.But wiith fuel prices being what they are ,(24mpg hwy,19 city) I'm thinking of converting it to diesel,I have access to a mercedes 5cyl turbo diesel & auto trans.I realize I'm going to have to go with heavier springs,etc. Does anyone out there have any experience with this? The truck has approx. 180k on it.thanx,tom(sprecher48)