Correct. Do NOT dismantle the upper cylinder head portion without first
removing the timing belt, cam pulleys and setting the engine to TDC and
locking the cams. Slacken the retaining bolts progressively 1/2 turn each
all the way around from the center working outwards diagonally- the haynes
manual shows the correct order.

Use some gasket remover or cellulose thinners to remove all traces of old
"gasket" from both surfaces, and ensure everything is perfectly clean before
you start taking it all apart and before putting it back together.

For re-assembly you will need the cam straps both ends (to hold the cams in
the upper portion and in correct position) a small mo-hair roller, the
correct Volvo sealant (NOT silicone!!) and 2 pull down tools, which screw
into plug holes 2 and 4 with which you pull the upper portion back onto the
lower portion and into position before you insert the bolts which hold it
on.Be careful and take your time that it is indeed pulling down square and
onto the dowels against the valve springs.

All the special tools can be made in a reasonable workshop- again the haynes
manual shows these in detail.

Torque the upper cam carrier down to the correct figure.

Use a new cam belt, and turn the engine over twice by hand and re check the
timing marks before you attempt to fire it up.

If you dont feel capable of doing this- leave it to an expert- i.e. someone
who has stripped the modular engine before- it is not something you can do
with a 3/8 spanner and flat blade screwdriver!!

Tim..