The answer is right where I told you:
"The complete geeks guide to turbocharging your b23F"
While it is relatively easy to turbo a car if you are mechanically inclined, and all the parts you need were factory made, most of the factory turbo cars were 740s. Likely the turbo on that b21ft is cooked or on its way. Fortunately you can get a chinabay t3 turbo online for peanuts. Most of the 740 parts fit, but some don't like the downpipe. Finding all the parts you need in a junkyard, and having them all work usually does not happen fast. It is not something you do if you have a time crunch, especially the first time. Most people collect the parts over a little while, and they usually end up with unforeseen problems and delays. Like the oil drain. Can you drill and tap a block or weld a bung on the oil pan?
Best way to do it is to aquire a complete turbo 740 for the fuel system, and the 90+ exhaust manifold cause they flow better. Finding an uncracked one is the hard part.
Your biggest issue is k-jet mechanical fuel injection. The b21ft used a bigger fuel system than the b21f, though both use k-jet which is REALLY hard to tune, and the b21f came with a fuel system that is in adequate for a turbo car, especially since tuning it is almost impossible these days. The fuel system is tuned with shims and changing fuel pressures, not with a laptop. VERY sensitive to correct, leak free vacuum system.
Turboing a car with electronic fuel injection is much better idea. All the parts for this come off of the later 740s as well as non-turbo 240s.
Off of the 240, you need all intercooler piping, intercooler, downpipe, manifold, turbo, guages, etc