What is necessary to swap in a 440 in place of the stock 360 in my 74 Trailduster.

Can I use the same cross member?

Would any big block 727 torqueflite from the era work?

Driveshaft different?

Frame mounts for motor mounts remain the same?

Not sure on crossmamber, but driveshaft is same as long as you get your bb 727 and swap the guts over from the existing 4x4 727 trans, so it will match transfer case adapter etc.

You need the big block truck motor mounts and the power steering brackets are truck specific

Rear sump oil pan.

Exhaust manifolds are truck only unless you use headers.

Ed

You may also need to change the brake booster to clear the valve cover and a good size radiator.

use 77-78 BB truck parts

3/4 ton small booster
75-up BB 4x4 truck mounts
rear sump pan and pick-up tube/oil dip stick/tube (goes in side of rear sump/plug hole in block pan rail)
2 center dump truck manifolds or 1 rear dump/1 center dump truck manifolds or hedman 79250 headers/they do not hang below frame rails 2x & 4x4
high mount PS pump/brackets
3 piece PTK linkage/brackets
non a/c pulleys/belts/hoses
77-78 3/4 ton 3 row max cooling rad (same width but taller) uses a larger stock aux trans cooler also 77-78 truck thermo clutch with 7 blade fan


swap/change out-put shaft in a BB 2x trans with the 4x4 output/adaptor/mount/xfer/xmember/drive shafts = bolt in

start saving for gas now while you build it.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ what he said +


Transfer case will dictate engine brackets, the divorced 205 case and shortie trans use the 4x2 engine brackets, the 203 fulltime case and trans adaptor will use the 75 and later 4x4 Brackets. either way your not going to be able to use a long tail(passenger car) trans as is , you'll need to modify it either add the shortie extension or remove the tail extension and add the 4x4 adapter and 203 transfer case.
Brake booster, just get the 3/4 or 1 ton small booster, you can make the D/W100 work, but your not going to like it.

A lot of really good info here guys. Thanks for taking the time to advise.

So I can use the adapter/xfer case setup from the small block 727 on the big block 727?

I'd be using the full time 203 setup that came on the truck.

Will everything line up on the cross member?

Yes. The only difference between the small block 727 and a big block 727 is the bell housing. Well, there are some internal parts in the Hemi and motor home 727s but as fat as length, they are the same.
A little nugget:
About 2 years ago I converted my 75 440 4 speed Power Wagon to a 727. The transmission was the same length there as well. DRive shafts are the same, transfer case adapter was the same...It was an easy swap.
Too bad you don't want a 4 speed setup. I'd make a really good deal!