The idea was you used the lug that produced the best width. Leave the other lugs unused.
I used an Ohmite 7.5K 50W and a 20K in parallel
https://flic.kr/p/f3yNXS
They are on sale at Allied and mount nicely with the original hardware.
http://www.alliedelec.com/search/pro...x?SKU=70024373