Getting opinions, I have a choice of engines in my stash, 74 440, 360 Magnum-380 hp, 360 reg engine, 5.7 Hemi. Truck has the original engine but need total rebuild $$ and it’s in boxes. Not trying for a resto, more of the rat rod thing, rust spots and ding driver. The reg 360 is still in a 92 Van with the overdrive trans (what I want to use). I can get a cheap adapter for the 440 from ATI. I want to be able to drive 500 miles if needed.
All the engines are new or real close to it and ac, power brakes and steering will be put back on.
Opinions?

My '81 stepside has a rebuilt 360. Runs great. About same gas mileage as the 383 in my road runner. 440 would be nice, but I'd love to have a 4 speed in the truck more.

For me it would be the 5.7 hands down, and keep the EFI. www.hotwireauto.com has a plug and play engine harness that flat works. Not cheap, but what is these days.
More power, better fuel mileage, reliable package. Gene

I sure love my 5.7L Hemi in the 'Cuda. I won't be surprised if I swap it into my Warlock some day and bump up the engine in the 'Cuda.

Go Hemi.

Was saving the 5.7 for the wife’s 05 Dak but I do have another that needs a crank kit. That engine would hook up to the 92 overdrive trans also. Trying to get away cheap but I’ll check into that plug and play wiring.

For my own stuff it would be a mild 440 all the way, I love the off idle torque with the big motor and I have 7 440's lying around and all the brackets to make it work, but in your case since you really want to use the OD trans I would go for the magnum 360 380hp motor with the OD trans (much easier than getting an adapter or doing a bellhousing modification to make the 440 work) and then run some lower gears in the rear end and have a good all around package, I believe most of your brackets and odds and ends from the 79 360 should pretty much bolt up.

Good points, I’ve had the 440 sitting in my garage for 25 years all stock with maybe 15,000 miles on it and really would like to use it. I’ve had 360s before and wasn’t impressed with their grunt. Truck has an 8-1/4 rear with 3.31 gears but I have a 73 Chrysler with a 2.90 something that would be a good road gear with standard 727. With the od trans I would use my 4.30 gear + the od would get it back around 3.0 for the street. The adapter is only about $80 so that is not an issue. Then I wonder if the 440 would tear that rear up? I have a complete 8-3/4 3.91 package plus a 9-1/4 3.90 package too. A lot of options, if fact to many!

You could probably get away with using an 8 1/4 for a while but definately upgrade to an 8 3/4 or 9 1/4.
If your set on a 440 and you have a good one I definatly would use it that low rpm torque you get out of big cubic inches is tuff to beat.
I have a 77 Ramcharger that I have a very mild 500 cubed big block with 3.23 gears and its a total blast to drive around town, no loose sloppy convertor and idles great sitting in traffic.

Yours sounds like fun, mine has the unleaded valves and runs on regular gas, came in my 64 Savoy race car and ran 7.77 best, of course it had good vert, 509 cam and 4.88 Dana, big tires all steel. Pulled it for a better 440 and been sitting there waiting.

If your Lil' Red Express has the original rear end in it, that should be a 9 1/4 and have 355's gears. I have a old 1978 Lil' Red Express that was my dads at one time and have owned a few of them over the years.. I had a extra Lil' Red 9 1/4 rear end and it's under a old 1937 Plymouth Truck right now.. ..

Almost sure it’s an 8-1/4 looks original but I’ll go check again. First time for these trucks so unsure whats supposed to be there, thanks for the help all.
Went and looked again, definitely an 8-1/4, perches on the top of the housing like it’s supposed to be