I was driving to work this morning and I downshifted and as soon as I downshifted everything stopped working it's not my Speedo and my overdrive switch doesn't work anymore is this a fuse or do you can someone help me out

 

Check the 10A Meter fuse.

 

check your fuse box. look at your manual if you have one and find the one that powers the speedo. most likely just a burnt fuse

 

The speedometer is the only mechanical gauge in the cluster (it's cable driven) which is why it's still working when all the electric gauges have failed.
As previously mentioned, probably a bad METER fuse.

 

so right now i don't have an extra 7.5 amp fuse, will it hurt if I threw a 10 amp in there for my drive home?

 

Probably not but if civilization as we know it comes to an end, you'll at least know your fuel level.

 

haha right on man, i didnt think so but just wanted to make sure. Ya know

 

You never did mention the year of your RX7. The S5 (89-91) FSM specifies a 10A meter fuse. Not sure about the S4 (86-88) series.

 

S4 88