Connecting Ag6 Bell Box To Optima Compact Panel

I am trying to connect a new Honeywell AG6 bell box to an existing Optima Compact panel. The Optima manual says connect:

T=  -ve tamper return  (TR- on bellbox)

A=  -ve supply  (V- on bell box)

But the AG6 instructions say for Optima XL4 connect:

A=  -ve tamper return  (TR- on bellbox)

T=  -ve supply  (V- on bell box)

I have an Opima compact but this is not mentioned in the AG6 instructions.

Are the Optima compact and XL4 wired the same?

I tried connecting as per the Optima compact instructions i.e.

T=  -ve tamper return  (TR- on bellbox)

A=  -ve supply  (V- on bell box)

but I have a constant tamper light on the control panel.

Suggestions please.

Have you checked to make sure it is not actually in tamper?