Let me clarify some things:
It is not the axle housing width that is different, it is the way the frame is set up with the 105 and the 100 series that doesn't allow a correct fitment.
The 105 axle housing for the front is exactly the same width as an 80 series: 43110-60400 (locking front axle). I confirmed this because I have one sitting in my warehouse getting ready for my 80 rebuild.
The frames of the 80 and the 105 are actually quite similar. It is the frames of the 105 and the 100 series with IFS that are quite different and doesn't allow a very good transposition of the two between each other.
Of course there are other subtle differences as well (5 lug vs 6 lug, etc.) but the issue really is mating the 80 series axle housing (which is a different and superceded number from the original factory production--the axle housing for the 105 and the updated 80 series is substantially beefed up--so much so that I wholeheartedly recommend the axle housing upgrade for 80 series owners) to the 100 series frame which is where the real issue arises (mainly because of fitting the 2UZ into the frame)--remember there never was a UZJ105, only a UZJ100. All 105's had either the 1HZ, the 1FZ, or the 1HD variants.
The 100 series frame is significantly different than the 105 series frame which is basically an 80 series frame at least for front axle housing fitment reasons.
Anyway, enjoy the pics. Notice how beefed up certain components are compared to regular 80 series factory housings. Connections points have been substantially beefed up, thicker bracketry, better and stronger welding, and a thicker housing as well.
Toyota learned from the abuse the Australians gave the 80 series components so when the 105 was conceived as the transitionary vehicle (getting the Aussies ready for the IFS coming with the wagons), they substantially upgraded the components. The 7x vehicles all share the new upgraded housings with different lengths depending on vehicle specifications.
The key really is to get a hold of a 105 frame and transfer the 100 series body onto it. A lot of work, but I think cheaper than trying to mate the 105 axle to an IFS setup 100 series frame.
Just to confirm my theory, the front lateral support is the same from all 80 series rigs as well as all 105 series rigs. Which to me means that the front of the 80 as well as the 105 was set up for I-6 engines of either diesel or 1FZ variety--both of which require a significantly different setup for support than the 2UZ engine does.
Enjoy the pics....
why don't you keep the 80 for heavy wheeling?
On big grades the SC would go flat at higher RPM and the 100 RPM's would continue to climb.
but there is when it ends
