Since the list would generally be huge and ever expanding I'd consider getting some stats on a few things before setting up all the posts. Of course take my advise with a grain of salt
Step 1: Figure out the average number of items in a bundle (rounded up)
Step 2: Create a post with all the formatting as you'll want it for the thread and see how many of those averagely sized bundles you can fit
Step 3: Set up posts only half full to leave room for additional bundles later
Optional: Look through the last year or two of bundles and take note of the letters their names usually begin with.
Names of anything tend to disproportionately lean towards just a few starting letters.
Use this knowledge to add extra space around letters which are the most common. This could be by only filling up a fourth of the posts or by leaving blank reserved posts in-between.
Oh and definitely cannibalize anything you can from the previous list!
This is one of those lists where Aerdian's spreadsheet formatting would probably shine because keeping track by hand will be one heck of a task
ninja edit: If we're talking
lilloulou's guide it looks like they did have the data in spreadsheets and offered to try and get those to a new caretaker. Granted that was a year ago so not sure if they still have them