Hot but Stable - Clutching at Straws

What I have is a mild 318 abt 280hp.
Compression is an accurately measured 9.25:1
New water pump
New 160deg thermostat - tested and checked out OK
Cleaned out radiator
7 blade fan with new clutch
New shroud
New hoses and spring in bottom
Tefba filter
16" thermofan pusher
New temp guage
Heads shaved so they are flat-meaning leaky head gasket very unlikely.

So in short I went overkill to make sure this thing don't run hot.
But it does.

It's not an airflow problem since it runs hot on the highway.
Well,it makes no difference highway or city driving.

It's running around 205 to 215deg but stable.
It won't go above and it won't pull down.

Timing is 16 initial at 700rpm and 35 total all in at 3000rpm and it runs pretty sweet,starts well.No detonation.
I've been pulling some crud out of the Tefba but certainly not enough to block it.
Switching on the big 16" electric makes no difference.

I've just put in a 195deg thermostat and will go for a spin shortly to try that.

Searching older posts gave me a possible idea.
Do you think the screen in the Tefba would cause enough restriction to force too much recirculated water back through the bypass hose?
There was mention of restricting the bypass hose to less flow to overcome too much hot water recirculating.
Has anyone done this with success?

How much total timing do you think this thing can withstand?
I checked with a mate since his engine is pretty similar to mine and his is 16 initial and 36 total.
He runs a tad cooler than mine around town but he's down to 180 on the highway which is where I want to be.

When I pull up the radiator doesn't feel as hot as the guage suggests so it is possible the guage may be reading wrong.
Otherwise maybe the water in the block IS hot but the water in the radiator isn't??

Since I'm pretty good with cooling I don't think this one will be one of the common problems so any left field ideas welcome.