there are other configurations of E-type mounts that allow up-down adjustments...
search: Shimano Deore LX E-Type Mountain Bike Front Derailleur
and Search: Shimano SLX FD-M660-E-type Front Derailleur
on ebay to see examples...

the Older LX versions may have a deraiilleur more suited to the larger chainring your tiny wheels need, since a lot of older MTBs used larger rings, and even those goofy oval rings...
and shopping around may find a road-curved Der that might be perfect.

personally, i'd try getting the CHAINLINE pulled in to correct things, if possible...
rule of thumb is 1/4", 6 mm clearance between the teeth and chain stay member of the frame... some have gotten away with 2-3mm... i always try for at least a 4mm gap

and Double Front Ders have a shorter tail than Triple ders...

and one more piece of info to consider.. square taper Cranksets are not all the same offset... i classify them as inny, middy, and outy... this refers to the position of the center of the spider to the inner chainring....