Man, That would be a difficult decision, The truck looks to me like it's pretty darn complete.

When I first got my truck I was dead set on rodding it with a V8, even though I thought the engine was the original 228 and the truck was a little rarer than most, but after seeing these old school inlines I started to change my mind.

Right now it has a 216 from a '41 Chevy, it runs, so for now I'll drive it as is.
Next spring I'll put my V8 in it(Because the 216 probably won't last long, it sat for 9 years with a crankcase full of rainwater)then I'll start looking for an inline that suits my taste for old school rods.

I've decided to enjoy the truck, no matter what anyone else thinks. I'll know when the truck is right by the way it makes me feel when I'm looking out that tiny windsheild!