'66 C10 Motor 283/350/455 - transmission options

[blackcloud45]

Hey all, would like some input on engine transmission choice for my project...

I have a '66 SWB C10, came stock w/ 283 and 3 speed standard. All original, bought new by my great grandfather in '66, given to my grandfather in '76, then given to me. Truck has been sitting since '86. I have taken it down to the frame for a complete resto. Not wanting to do a 100% back-to-factory stock restoration but really want a good, solid truck that I can enjoy for many years.

As part of my resto I've decided to perform the power steering conversion as well as front disc brake conversion. My grandfather and I talked prior to his passing and he said he always wanted to put an automatic tranny in it. I agree w/ that idea.

Let me kind of describe what I'm looking for. I'm not particularly worried about gas mileage. I drive a Honda for that. I'd like a good, dependable motor w/ enough power for a good seat of pants feel when you get on it. I grew up working on cars in my grandfather's shop but have no formal education as a mechanic. In other words, I feel pretty handy and am not afraid to tackle most projects. Having said that, (and the more I have to work on newer cars) I don't have enough experience diagnosing newer vehicles. I attribute this to the excess of sensors, computers, wiring, etc prevalent on newer cars. With the exception of upgrading points to a more modern ignition, I really am not interested in adding any of that crap to this truck. While stripping the frame I marveled at the 4 wire harness that I found. Did I say 4 WIRES? Awesome. In other words, no injection, sensors (except for basic temp, oil, and battery), no computer, etc.

My engine options as I see it are as follows:

Rebuild 283 - Enough power? Enough potential for power without pushing engine too hard? Doesn't seem to be a wide selection of aftermarket stuff made specifically for 283. I know some 350 parts will work, but are they optimal for the smaller engine?

Buy crate motor - Not interested in rebuilt crate motor. If I'm going new, I want all new. Probably the same cost as rebuild (or close enough to make difference negligible). Concerned w/ Mexico block. Most likely warranty will void due to my installing (as opposed to certified shop) and being invalid vehicle for engine? New and lots of happy success stories w/ the 260 hp and 290 hp GM models. Camshaft worth the price difference? I dunno. A couple of horror stories too.

Rebuild on hand '68 Olds 455 engine - I've owned this engine a long time and know the history. Big motor w/ decent HP right of the gate in stock form. I already have Edelbrock Performer manifold and Carb. Heads and a mild cam and I'm there? In other words, not working as hard to meet same goal. I've owned several big block cars and there is just something special about cubic inches. Swap issues? Mounts might work or I've read about the 350 diesel mounts so I don't think that's an issue. I think Cutlass headers will work. This engine also has matching TH400 tranny bolted to it (also a candidate for rebuild). Concerned w/ weight difference w/ regards to springs and / or potential for frame damage? This motor is HEAVY. Distributor clearance? Fan shroud issues? Power steering bracket and pump already present.

Did I mention I'll be running AC as this truck was ordered w/ AC from factory?

Transmission - I'm pretty open. No experience w/ OD trannys. Ran a bunch of TH400's though. Rear end gears 3:73 FYI. Do I even need OD?

Sorry for the long post guys and thanks in advance for your time / responses.