i am doing the same thing.... i have a mark viii motor also. heres what i have done...
you have to get a tubular kmember, new exhaust,t-45 or t56 tranny, motor mounts, hydroboost, intake, wireharnesses up the waazoo, wire it all together. and soo much more. its best to buy a wrecked car and do it that way... but i cannot do that because i live in an area that its illegal to have an inoperable vehicle on your property.
i am currently fitting the newer dash to my car. thats a wholenother p.i.t.a.!
with the mark viii motor, the tb is in the back, you have to get your hands on a cobra intake or a 97-98 mark viii intake that the tb is located on the side.
hope this helps