Flat Top Plenum Gasket?
 

Just got a flat top manifold ordered. It does not look like it comes with a plenum or IM to head gasket. Are those the same gasket as USDM? I will be planning on blocking off the EGR as well, would there be anything else to do while I have it off, or during the swap?

Buy a EGR block off kit, they fit 94-05, they're cheap, but also easy to fab, trace gaskets and cut. Reuse plenum and EGR gaskets, I've never had a problem doing that. The plenum is square top specific, I'm sure someone will pop in hear with a part number, but I've always reused. EGR gaskets and manifold-to-head gaskets are same as USDM. Reuse intake if it's not shedding it's black, or buy a new one.

Just the first ones I found:

https://miataroadster.com/products/o...block-off-kits

https://flyinmiata.com/products/gask...aM9Gd5dr_OE7R6

Thanks curly. I plan on blocking off the EGR with a plate, I have blocked off the EGR on the RX the same way since its just 2 bolt holes and I reuse the gasket.
Good to know about the plenum gasket being different, I was going to order a USDM one but at $40 a pop I will double check to be sure. I always put new gaskets in as it is just cheap insurance.

Flat top plenum gasket

Aha, found it:
Plenum Gasket - BP6Z-13-135 found here
Intake Manifold Gasket - BP4W-13-111 found here
EGR gasket - BP4W-20-305 found here