At present I have no exhaust system whatsoever for my '72 A65T.
The proverbial blank canvas.
I'm thinking about factory shaped downpipes but the custom non header pipe version.
But looking at the design of the A65 head with it's splayed out push in exhaust ports, I'm thinking that the exhaust balence pipe is probably responsible for actually holding the header pipes into the head more than any flat steel brackets.
If I fit the non balence version am I going to struggle with headers that just won't stay put ?

I've only got riding experience of Triumphs with clamp on (push over) pipes.
Even the T140 I had was converted to push over stubs, so push in pipes are a new experience for me.