I've got a b18c swap in my 93 teg and like you said everything does bolt up with no problems. Try to get a tranny from an Si since they have shorter gearing. If you have an after market header like DC it may actually sit on the cross-member and you'll have a tuff time getting the front tranny mount to fit correctly. We couldn't even get my mount to fit so we only used the other three. Also, if the exhaust is still on the LS than you might have to get an extra pipe fitted between the cat and the header, or cat and exhaust so that everything will reach each other. I don't think there will be a problem if you have an exhaust from/for a GSR though. Good luck.