Is it front, mid, or rear sump? That may dictate what you can use it for - most swaps are easier with the rear sump, so you may want to think about picking one of those up.
Many people retain the original distributor based ignition, but I'm not a fan of it. I would lose the distributors and put a COP ignition on it, and run the whole thing from an MS3, or similar.
W58's used to be dirt cheap because nobody wanted them for their Supras; what happened? It's probably an Aisin tranny, so it'll be in other cars - all you need is the bellhousing, which you already have.
Try to get a set of early SC400 exhaust manifolds; they're a little better than the ones you may have with that engine. There used to be 1-2 aftermarket providers of headers, but they've probably all gone under by now. Australia had a couple of providers for cast manifolds that were much better than the stock - don't know if they're still around.
If you don't have to meet emissions in your state, I'd pull off the EGR, but I'd leave the crankcase ventilation system, but run it to a good catch can. There's a little coolant circuit that runs through the throttle body which doesn't hurt anything, and you'd probably find useful since you live in a freezing climate. The pressure drop across the throttle body can cause quite a cooling effect (Joules-Thomson), and if you're at, or near freezing, you could experience a freezeup of the butterfly.