Speaking of TB V?

[NHGuy]

Where does the distributor ground attach? i just ran my new engine and it's not running right. And I do have and extra black wire with a loop terminal right by the distributor.

 

[Bondo]

Ayuh,.... There oughta be a little hole, Up from below in the main housin',....

Maybe midway 'tween the rim, 'n shaft,...

 

[Fun Times]

Some models had a longer screw on one side that held down the ignition sensor and was attached with a nut under the distributor housing.

See item numbers 7,http://www.mercruiserparts.com/bam/subassembly/31770/1939/50

7	10-66686	--SCREW, (#10-32 x 1.00)		ACT		$1.30	$1.27	1
7	10-72202	--SCREW, (#10-32 x 1.25)		ACT		$2.30	$2.25	1

 

[NHGuy]

This ignition originated with a 1997 4 barrel 350 Mag which later had heads done at a Mercruiser shop. I bet they used the 10-32 x 1" hold downs then and left off that ground.
There is a ground on the distributor by the ECM and knock control module. But since the distributor is made of aluminum I am going to do the 1.25" through-bolt and add that ground. Aluminum isn't the best conductor.