It's been 7 years since I've replaced my coolant hoses. About 35-40k. The top hose is only about 2 years old, it's the reroute hose from super miata. The lower hose is a fm silicone hose. Fm is out of the lower hose. I bought the kit with all the hoses. Should I use the new oem lower hose, or get a silicone one?

 

Get what you know fits with your intercooler piping.

I know that with my set-up, OEM works, but FM does not. That's because I built around the OEM, I suppose.

 

^^ Yep, what the Mak says.
I bought a full FM turbo kit but ended up using a new Stock Mazda lower rad hose since it fit way better around the intercooler hoses than the FM silicone one did.