Don't get me wrong i had a 7.3 idi tell the auto trans gave out had close to 400k on it.If hes looking for big power and easy swap a cummins is best a powerstroke would bolt right in but would take a parts truck to do it right.

 

I had a '95 F350 Powerstroke and it drove me batty. I still have a '97 E350 powerstroke that's just as much fun.

My buddy has IDI's and I'd much prefer them for the mechanical injection system alone. (The cramped fit in the chassis is about the same though). The factory 93-94 IDI turbo is a good place to start. There's a number of desirable internal differences on those.

On the PSD, injectors and hpop are regular replacement items. Probably every 200,000km. Should do head gaskets and studs at that age too, since the cylinder pressures will come up a bunch. Might want the extra insurance of replacing the injector seats too while you're at it. Wow that's a good chunk of change... maybe should do a valve job too. Glow plugs, UVC harnesses, and VC gaskets (electrical pass-thru type) for the icing on the cake.

But I digress... got myself a few Cummins 1st gens and couldn't be happier.