Throttle bodies

I have a 88 mustang Gt 5.0 I want to install a 70mm throttle body can i just take the stock one off and install this one or i need to change somehting else. Gaskets and the EGR plate are a must too?

1988 was the last year of speed density I think. So you dont have a mass air flow sensor. I'm not positive but I kinda doubt that the speed density system will handle the change very well.

Well i'm not 100% sure what it will do with the speed density but i believe you will be fine.
You DO need to change the egr plate and yes you will need the gaskets too.
Unless you are going to change the heads, cam, intake OR go with a supercharger or turbocharger i suggest sticking with a 65mm. Even with heads/cam/intake some people still see more power with the smaller throttlebody.

Thanks for advice ill stick with the 65mm throttle body eventually im going to go with a supercharger.