Doors and Windows - Remove bifolds and wall between them, replace with bypass

In our master bedroom we currently have about 9 feet of shallow (i.e. not walk-in) closet along one wall, which is accessed by two 4-foot wide sets of bifold doors, with about a 7-inch wide column of wall between the two sets of bifold doors. With the bifolds on both sides of the center column open, there's really an 18-inch wide barrier to the closet. This makes it difficult to get at the clothes behind this center barrier. I'd like to remove this center column and replace the bifold doors with 4 sliding bypass doors that could all be pushed to either side, stacking up behind each other, allowing access to 3/4 of the closet at one time.

Obviously the 4 bypass doors should be thinner than standard doors so that their tracks will all fit on the wall along the top of the closet opening (about 4 inches wide); perhaps 1/2" or 5/8" plywood that I could paint. But I don't know if this will even work: can I get tracks/harware narrow enough to accomodate thinner doors spaced closely together? Is there anything to consider in removing that center column of wall (I've been told it's not load-bearing)? Any particular gotchas or things to watch out for? Is this just a totally ridiculous idea?

Thanks much for any advice or ideas!

My guess is that this center post is supporting 2 individual headers -- the 2 four foot openings. Assuming that you have been told right -- that this is a non-bearing wall -- then taking out the post AND the headers, and replacing them with one CONTINUOUS header shouldn't be that big of a thing. A 4X8, 4X10, or a 4X12 will work fine.

As was mentioned, at a min, use a 4x8 and this should be a reasonably uneventful installation.
I would also recommend that you select a more stable plywood than that standardly available, such as a marine or better cabinet grade, something which is not as prone to deforming when painted.
Consider staggering the panels width to allow for finger pull on both ends stacked.
There are also track and truck hdw. which will allow you to place 4 individual tracks, side by side, and carry the weight.

Thanks to both lefty and Snoonyb for some good ideas. I do have another question, though:

There are also track and truck hdw. which will allow you to place 4 individual tracks, side by side, and carry the weight.

Do you know where I could get these individual tracks? I checked our local Home Depot and they only have tracks that accomodate two doors on a single piece of metal.

Thanks again!

To use the tracks the HD sells, buy 2 -- each one half the width of the closet opening. Simply align them across the header. (A long level or other straight edge works well.)

OK, but I'd really rather use the individual tracks that Snoonyb mentioned, because the dual-tracks sold at HD are set for doors that are "normal" thickness (about 1.25 thick?). The entire track is 3" wide so of course putting two side-by-side to accomodate the four doors I want would need 6" of wall depth. I only have about 4.5" of wall depth. But since I'd like to use thinner doors anyway, I might be able to make it all fit if I could find the individual tracks. Does anybody know where I might find them? Thanks again!