There is another trick with that enlarger that you can use so you do not have to buy another lens. It is a bit of a process, but it works. You can raise the enlarger by putting blocks underneath each side of the base rails. Then remove the baseboard and print on the table. The problem, if this is a temporary setup done with imprecise blocks such as 2x4s, is alignment. After you rig it up on the blocks and test to make sure you have enough enlargement, you might need to use some shims for the blocks – strips of card stock will work fine – and a way to test your alignment. I use a grainy negative to fix my B22 when it inevitably slips out of alignment every now and then. (They are cheap enlargers. Yours is much better; once set up properly, it will rarely, if ever, go out of alignment, and if it does, it is easy to adjust.)
With this enlarger, you can also very easily tilt it backward for horizontals. If you have a rolling metal filing cabinet, you can use magnets to hold your paper in place there. Again, with a temporary setup, alignment is a pain, but it can be done.
Ideally, you have a special table with two shelves (top one removable) set up permanently. When using the top for normal printing, the bottom serves as a storage shelf for your paper, proofer, etc. When printing big, take the top shelf off and the bottom shelf serves as your baseboard.
