Richard,

You have a fair amount of used options within the Montero community. There are several active parts Monteros on the Facebook pages, just have to get some contact there.

I have personally installed Gen 1 LWB springs in a SWB for a gent from Sacramento. While he reported a slightly stiffer ride, he did not find any lift from that conversion. He later installed some Gen 2 springs and visited me, proudly displaying a marked 1.5" raise over stock. This is a drop in conversion, but must use the rubber isolaters from the donor Gen 2. I measured against my 87 Raider leaf spring and was so jealous of the clearance his V6 Montero had.

Cheers,
Russell