And I don't know which one I want!

Well, I know I want the best one for the job, and ideally I want the one used on the pd150 as I'll be using the stronger pd150 headbolts when my new head is fitted. The three gaskets are

1.45mm 1 hole

1.53mm 2 hole

1.61mm 3 hole

Now I've no idea what holes are referred to.... But I will need to know which one to get fairly soon.

Thanks for any guidance.

the holes refer to the piston protrusion above the cylinder block surface

it is explained in the Haynes manual section 2D pages 20-21

the sizes mentioned in the Haynes are

0.91-1.00mm piston protruson = gasket hole 1

1.01-1.10mm piston protrusion = gasket hole 2

1.11-1.20mm piston protrusion = gasket hole 3

piston protrusion is measured with the use of a dial gauge mounted on the block surface , use the highest piston protrusion to determine the correct gasket thickness

So I can't buy one in advance? :eek:

This isn't uncommon. If you want to chance it go for the one in the middle....

Or buy all 3

Wrong thread, sorry!

Or buy all 3

Common sense prevails!

Get them from a good motorfactors and you can take them back if wrong.

The original gasket will have a small web on it with some small 5 or 6mm diameter holes in it. It is these holes that are referred to. If in doubt post a picture of the gasket that is removed.