Well, it is done - Chico has met the mammoth!!!!!
Others outside in car so no interference, treats, clicker, harness, garden!!
I took Brice outside and did a bit of focus work with the clicker, then I casually opened the kennel door but threw Chico a handful of food into the kennel so he went backwards rather than bursting out into Brice's space.
I went to sit calmly on the WET seat and continued doing the clicker work with Brice. Chico arrived (ps I know he has food manners when using food like this and Brice knows the exercises concentrating on food well) on the scene as he realised there was more food possibly in the offing

.
Ok - what is the big thing???

Or perhaps more importantly hand out the sausage!!

Brice was surprisingly intimidated as Chico wasn't really making eye contact or overtly 'noticing' him

But bravely came closer (for sausage

)

Then he decided to risk sniffing

...

While Chico remained focussed on the possiblity of food

or more food??

Brice then retired inside and the victor claimed the garden!!!

Brice is now in the kitchen, Chico is alternating between exploring the house and lying on my feet.
I was expecting Brice to be a lot more confident and I will need to get the boys together a bit more as this anxiety has surprised me. It is better than aggression obviously but I can't have Brice stressed either.