i have a pm6 out of a 91 civic si and then also a obdo pr4. i was just wonderin cause my buddy is doing a sohc v-tec swap and he has both. i know he should just covert to obd-1 but some people just dont have the funds like everyone else here on honda-tech. so dont reply saying do it this way or do it that way just tell me if there is a difference, and or what one is better for that swap.