Best way to install laminate plank over imperfections?

My father in law is unexpectedly coming to live with us for a few weeks. He's been in the hospital for months, and is getting discharged tomorrow. We found this out yesterday. He can't go home because he can't do stairs yet, nor does his knee bend enough to use the chair lift yet. So he is coming to our house, which means that we have been ripping up carpet and nails so that he can use our downstairs guest room. 

The OT said no carpet. The hardwood that the carpet was covering is definitely restorable, but a bigger task than we can take on in 2 days. So we are doing laminate "hardwood". This stuff: https://www.menards.com/main/flooring-rugs/laminate-flooring/laminate-flooring/ellison-house-brookview-7-1-2-x-47-1-4-attached-pad-laminate-flooring-19-63-sq-ctn/men01-04/p-1569220133130-c-12442.htm

There is one bulge in the hardwood; I've tried to put a relief cut, but it is in the subfloor. 

It simply cannot be rectified right now - we don't have the time or experience to do anything about it. We have to live with it (house is 95 years old, hardwood at least 65 years old). 
 

So... what is the best way to install this flooring over it? Should we try to get a seam at the top of the bulge, and run it the same way as the hardwood? Or run it length wise across it? Or am I overthinking this and it doesn't matter?

As long as there is no movement around the bulge you might get away with it. The problem comes when the lock grooves break. It can be tricky getting the pieces down and locked with the curve but do-able. You might try to assemble a few rows to put down at once to clear it.

4" belt sander with super coarse belts.

Sand it down,

Been there, done that.

Even a 3'' belt will work.   Buy a throw-away one from HF and a bunch of their belts.

My bus has a very uneven floor so I put 1/4 inch cork down under the flooring. You can smash it down over humps less than 1/4 inch, or cut around the hump and use a little floor leveler. Put it on tape or plastic if you want to pull it back up easily.

Had a major fail doing this over an uneven plywood floor.  Seams open up, looks like crap.  Will end up ripping it out and carpeting but for now it is an exercise room so  I just ignore it.

How much of a bulge are we talking about?

I did a floating wood floor in my friend's pole studio and that floor was a freaking disaster.  I zipped a few screws in where I could to try to tighten up the subfloor, but there were areas that dipped down and bumped up, sometimes inches

The whole thing was also a drop of about 6 inches from the left to the right there in one part of the room, but only about 7/8" at the other end.  Lots of water damage and building-settling.  Being a pole dance studio, it needed to be able to sustain a pretty decent impact, especially from some of the, uh, heftier patrons.  And two years later it's holding up pretty well still.  Your flooring will be able to accept a deviation of a certain number of inches over a certain number of feet, so it's about trying to smooth out some of the bigger imperfections over a wider area - kind of like laying railroad track where you have to start approaching a grade miles ahead to start building it up.  I got a couple rolls of thick roofing felt and used that under the planks.  I'd start out at the high point and lay the felt in increasing heights away from it.  Or, lay it on thick in a low point to build up the hole in the floor.  The felt is moisture-resistant and doesn't compress, so it'll keep a good, solid underfoot feel over time.  In the end, the floor still isn't level from left-to-right, but it is flat and all the joints have been holding up well.  I just realized I don't actually have  good picture of the whole finished room, but if you pardon my mess:

Purple Frog (Forum Supporter) said:

4" belt sander with super coarse belts.

Sand it down,

Been there, done that.

Even a 3'' belt will work.   Buy a throw-away one from HF and a bunch of their belts.

This or a jack plain was gonna be my suggestion. 

Literally been there done that and fixed it... So...

• Dont assume that the floor will level itself out gradually or find a level.  It wont.
• If the floor is not razor flat, like 8 foot straight edge tells you its flat, lay some thin closed cell foam down first to help dampen the noise of the floor and let it "sit" a little bit.

I just pulled up 450 sqft of laminate floor in my uneven concrete basement (could not use self-leveller because I wanted to maintain the floor drain and conical floor shape) and tiled the whole mess with 2" hex tile.  Should have just done that from the get go.

You need to either set a level floor over the top of existing, level your existing floor, or go with a different flooring option that will conform better, maybe the adhesive backed lick n stick vinyl tiles.  

Belt sander for the highs and roofing felt to build up the lows.

Did this in my last house to mitigate the nature of a 65 year old subfloor.  Worked OK, got it within the spec for the flooring but in hindsight it probably would have been quicker and more solid to just rip up and replace the subfloor.