6.2L Starter Fastener Size Questions

[NMC_EXP]

My M1009 will not crank. I've done the troubleshooting and determined everything on the cabin side of the firewall is OK. I replaced the solenoid under the dash as insurance. and will do doghead's upgrade ASAP. I intended to replace the starter with a new gear drive unit on general principles anyway - this failure just moved it up the list.

I need to verify that I have all parts on hand to change out the starter this weekend.

I will check the wires, cables, ground strap etc for problems after I drop the starter.

SITUATION:

The p/n 14028931 BRACKET, ANGLE is missing from the vehicle.

The heat shield (part # unknown - does not show in the -20P) is rattling around loose between the starter and exhaust manifold and the bolt which held it to the block is missing.

--I've ordered (2) BOLT, CLOSE TOLERANCE p/n 15544950 from GM.

--I've ordered (1) BRACKET, STRAIGHT p/n 23502557 from GM

--I've ordered (1) SPACER PLATE, p/n 23500396, discontinued by GM, ordered from Vintage Parts via GM dealer.

QUESTIONS:

(1) Need to verify the bolt size which holds BRACKET, STRAIGHT and I assume the heat shield (?) to the block. From what I've read it is a metric M8 x 1.5 x 20mm long. Is that the correct size?

(2) Need the thread size of the BRACKET, STRAIGHT mounting stud on the gear reduction starter from DB Electric so I can get the correct nut.​

Thanks

Jim