actually if you can get it for 3G than do it, you can turn around and sell that GSR tranny for at least 800-1000bucks and then find a cable trans for about 3-500bucks and make a little profit. You could also sell the axles for at least 300 bucks or more and pick up some 90-91 integra 5speed axles from the parts store for some more profit. Use this profit to pickup a motor mount kit and your conversion harness.
Spend the money and use the HASport cable/hydro conversion. Why have a gs-r swap and not use its potiential? If you are willing to pay the cash for a motor to 90% sure you will go all motor with, get a tranny that will be better. If you do the cable/hydro conversion, you can get an itr tranny (best all motor tranny).