[glennpm]

- First clean all the exhaust manifold holes out.
- Using two long bolts, 3/8 and 7/16"; hand thread them in the block and measure the protrusion under the head or to the outside of the bolt head
- Deduct 1/8" to 1/4" from the insertion length
- add thicknesses of manifold flanges and any washers or lock washers if you plan on using them
- buy or custom cut the bolts to the dimensions you calculated