Yes,it will fit 1680-2388.I bought a new standard size this summer for my 1680 and it was about $900.00 including freight.I think with the higher extensions it was about $1200.00.
PT: Sloans Express catalogue has the same order number for 1688,2188,2388 for Mauer extensions. $850 in 2004 book. If for some reason they don't work I might be interested in a set for a 1688. CW
