383 440 swap. Same flywheel?

To review.
The car came with a 383 and 833 of unknown origin. Who ever put it together shortened the input shaft somewhat. I would think it is because the 383 was not drilled deep enough.
They also did not put a pilot bushing in the crankshaft.
My intention is to use the transmission as it is with the register bearing, 53009180.
(The register bushing is not available anymore. 4338876)
I used the 383 with flywheel to make a fixture to drill the 440-cast crank for what remains of the input shaft.
I found a bit of scrap tube with an ID of 7/8 (.875) I used copper pipe with an OD of .875 as a guide to line it up with the existing .875 hole in the 383, clamped the tube (see previous pictures of rough idea) and tacked it on angle iron.
Pardon the welding. I didn’t want to risk burning into the thin tube.

Then I transferred the “jig” to the 440 and started drilling. The long copper pipe was used as a depth gage. Note the scribe marks on the brown copper pipe for depth measurment.
I take one at the top of the hole and one at the bottom shoulder.
I bought this 7/8 bit. I saw it marked “USA” in the picture before ordering it.
[ame="http://www.amazon.com/dp/B001TREZRC/ref=pe_175190_21431760_M3T1_ST1_dp_1"]Amazon.com: Champion XG12-7/8 Black Gold 7/8-Inch Silver and Deming Drill Bit: Home Improvement[/ame]
Champion XG12-7/8 seems to be a good bit. I didn’t want to risk China stuff.

My idea is that this hole will certainly not interfere with the input shaft using a register bearing even if it is missed drilled. That was suggested as an option. So the hole is larger than the .750 input shaft.
But I do not think that it will be the case that it is not centered fairly well.

And I was trying to get the hole size close enough to the bushing size of .940 OD. (That is what the parts list it as).
If later, if I wanted to use an input shaft that hasn’t been shortened, I hope the hole could be reamed up as necessary to accomidate a bushing.
Or the stock bushing OD could always be turned down a hair to fit the .875 hole.

Now my dilemma is this. The pilot bushing length is given as .880 in the parts specs.
How deep does the hole need to be to accommodate a bushing IF later, I decide to use a pilot bushing instead of a register bearing?
In other words I don’t have a good shaft length to go by and can’t find dimensions on the web. How deep does the hole need to be? I’m assuming the installed pilot bushing would be flush with the end of the hole.
I would like to drill the hole deep enough this time for that and not have to do it later IF I used an uncut input shaft with an appropriately sized bushing.
I’m about at .8 something deep now.