Fuel Filter to Block bolts

[Bensdexta]

Can someone tell me what size the bolts are that attach the Fuel Filter assembly to the engine block? My filter is marked AC on top.

That's bolts 17 or 18 below - what's the difference?
Looks like they are 5/16"-24, but how long should they be?

Also what about part 15A - described as 'SPACER, Oil Filter'? Should it be present and if so what is it made of?
TIA

[russelm]

Mine are fitted so cant guess the length but I recall that they only protruded by 15-20mm or so (guess you could measure them based on that)

They are two different lengths though as the thickness of the casting where they bolt through is different.

Mine did not have a spacer fitted.

[Bensdexta]

Mine are fitted so cant guess the length but I recall that they only protruded by 15-20mm or so (guess you could measure them based on that)
They are two different lengths though as the thickness of the casting where they bolt through is different.
Mine did not have a spacer fitted.

Many thanks.
Armed with that info, I think I've found my bolts. Mine are both the same length as I have the later AC fuel filter bowl - just under 1" long inc the shoulder. Don't believe I had a spacer either.