I’ve concluded that it’s essentially impossible to install the motor and trans as a unit with the core support in place. During the twisting and shoving process I managed to drop it and smashed the oil pan on the cross member. After I got it into place I crawled under and it looks like the oil pan is sufficiently pushed in to affect the oil pickup. It’s coming back out without the trans

I pulled & installed Pontiac engines, with TH400 trans bolted to 'em, many times, in our 1st gen drag cars. The 1st few times, the TH400 was actually a long tail.

But, I always had the car jacked up off the floor, so there'd be plenty of room to not only install engine/trans, but to also install headers. So, if I can do it, anybody can.

When I 1st did it, it was the very first time I had installed a Pontiac engine in anything. I was not a good, experienced mechanic, at all. Everything for me was sort of "trial & error", with lots of emphasis on "error".

The struggle is real, sorry to hear about the oil pan. The problem is as I am sure you know with the release on the cylinder, sometimes it seems they are all or nothing when releasing. As far as putting the 2 in together that is why I always use either chain falls or if available one of the arms on a 2-post lift. The problem with a lot of the available engine cranes is the reach and height are not enough when installing the 2 together without making it a 2-person job and a struggle. With a 4 speed like yours it's so easy to install after with the 4 bolts it's not even worth it.

Tub must dangle the motor from one end. Yeah, I was doing ok until I lowered it and the hoist lurched towards the bumper and caused me to not be able to stop the drop. The bumper sticks out a llong way. You have to go at it from an angle

"Tub must dangle the motor from one end..."

No, not at all. I just bolt 1 piece of chain, diagonally, & place the hook close to where the carb mounts. You can easily change the angle, by moving the hook along the chain. You can insert screwdrivers in the chain, on each side of the hook, to keep it from moving.

The pics show how I installed a 455/TH400 into my last 2nd gen Bird. Didn't even jack it up, for the initial install.

Because the nose stuck out so far, the arm wasn't long enuff. So, I grabbed up a handy piece of round pipe to make an arm extension. Actually made the arm longer than it had to be.

If a longer arm makes it too front heavy, there are lots of ways to add counter weight to the rear of the hoist. Obviously, the safest way to do that would be to get it weighted correctly, BEFORE actually putting the engine/trans over into the engine bay.

I'd pulled a 455 out of my '74 Ventura bracket car, with this same hoist, without needing an arm extension. But, the Ventura front bumper didn't stick out as far as on the 2nd gen Bird.

Back in the old days, I pulled/installed engines with my Dad's chain falls, hangin from an overhead beam in my old shop. But, the hook-up to the engine I used was the same.

All set. I was able to save the oil pan with a little pounding. I had another oil pan but it was a late 60's pan without the baffle and I wasn't really looking forward to welding in a baffle.

Much easier to deal with just the motor. The trans slid right back into place.