Any insight on left side chamber hood jams?

There were some incidences of that happening with some.  Could you provide things like what cartridge and bullet being used, recoil setup, have you tried other magazines?
It could be that the extractor is holding on to the spent cartridge too tight and that pushes the new cartridge to the side...

21lbs Wolff recoil spring kit.   Montana bullet company 200gr wfn pb.  I know this bullet has a wide metplat but I had it shooting reliably.   I did have the slide apart the other day to clean.  Different magazines, same jam.

The issue occurred after you had the slide apart to clean.  You might want to check the extractor some, place a spent casing underneath the extractor and wiggle to see if it is too tight.
By chance did you place a cartridge in the chamber and drop the slide to go into battery?  This action can damage or bend the extractor, more so worse on the 1911 guns.

I dont ever put rounds directly into the chamber.  I will check out the extractor.  Is there a spec on how tight it should hold the case?

For a 1911, tight enough that a round will stay if you lightly shake the slide, but not so tight that the round is obstructed from sliding under the extractor hook.

Let me make sure I have the facts correct.

Pistol was working fine
Slide was detail stripped for cleaning and re-assembled
Pistol now has a distinctive jam

This does implicate something not quite right in re-assembly, but coincidences like this have left me chasing ghosts too.  First step I would certainly take is take the slide back down and meticulously put it back.

Thanks for the replies.   I'll strip the slide down again.   I've shot a 1911 for years.   Don't really like all the plastic pieces in the slide, but if the whole pistol is plastic I guess I'll have to get used to it.

Took slide apart.   Small spring under the firing pin safety plunger was mashed in there sideways.   Thanks again.

That'd do it.  Is it recoverable or do you have to order another?

It looked fine.  Won't get to shoot again for a few days.  Thanks again for all the replies.

Thanks sqlbullet.  Shot it today,  feeding again.