Audi S4 V8 Timing Chain Problem and Repair

My 2004 Audi S4 V8 has a bad rattle on start up. Mechanics quoted £3,000 + £900 Parts to fix it but there might be a cheaper DIY fix...??

The kit of parts I bought were as follows (OEM part Refs):
A079103161D Gasket x 1
A079115111A Gasket x 1
A079103175C Valve x 2
A079115540A JET x 1
(0ptional)
AN90959701 Seal ring x 1

Видео Audi S4 V8 Timing Chain Problem and Repair канала Magic Smoke