[Dodger]

Well for starters, welcome aboard! I think I can answer some of your questions. As far as power, the DT466 will certainly be better than the 6.9l you have now. The Dt466 is an inline 6 cyl turbo diesel that has been around for a while. I own a 4700 with a DT360 (kinda like the 466'd kid brother) and it will out pull my 7.3IDI all day long. It gets better fuel economy and makes more power than the 7.3 in my E350. Depending on what year the engine is and what fuel system it has will dictate what you can do for more power. I shortened my frame from about 30 feet to 12 feet behind the cab to accomodate my old ambulance box. The drive shaft was a pain, but the guys here were great to deal with and helped out a bunch with all my questions. I ended up buying the complete International service manual set for the 4000 series trucks. They cover from 87 to 94. So if yours falls into that year group hit me up for any specific info and I will scan the pages you need. Good Luck,

Dodger