I paid $1250 for the engine and transmission… then I got a lightweight flywheel for about $400, and the harmonic balancer ended up being about $80 or so I think. As you say, you can save money if you can do your own engineering and installation of parts that were not put together that way by Ford.
The figures quoted in my previous post were for brand new parts. Tom’s kit in particular is a bolt-in item, using a low-volume production casting specifically designed to locate the shifter in the stock Tiger hole, and everything else required to make that happen. You also get an aftermarket transmission with ratios not available in an OEM (Ford) configuration, so as to optimize things for the diff ratios commonly used in Tigers. If you tried to duplicate his efforts you’d be out far more than the 4k figure…