obd2 to obd1 cost?

how much would it cost to switch obd3 to obd1 in my civic. I want hondata the s200 but have to switch to obd1 but im thinkin its gunna be more of a hastle than really worth it when i can just get the greddy blue box.

sorry obd2 not obd 3 my bad

I don't think it's legal to make an obd-2 car obd-1

www.hasport.com sells a conversion harness to do it, i think its like $250