i posted this already but i think i posted way to much and it pushed people away..so here is the simplified version: i want to put a navigation/LCD in place of my speedometer/intstrument cluster that can show can show speed too. possible?

1) can i put a nav screen in place of speedometer?
2) what nav shows speed?
3) would i have to leave any gauges?

here are some pics, altho most are concept (and far more advanced than what i'm looking for) its just to give u an idea
1, 2, 3, 4, 5, 6, 7