I have two gauge pods for sale.
They are both for mustangs but you may be able to make them work on something else.
One is a triple 2 1/16 autometer A-pillar BN in box. $15
the other is
a triple 2 5/8 pod with a cut out for a 5inch tach. $10
this is used, screws into the dash of a fox, but like i said you may be able to make it work on your application too.